Что такое error automation в vba excel

Return to VBA Code Examples

This tutorial will explain what a VBA Automation Error means and how it occurs.

Excel is made up of objects – the Workbook object, Worksheet object, Range object and Cell object to name but a few. Each object has multiple properties and methods whose behavior can be controlled with VBA code. If the VBA code is not correctly programmed, then an automation error can occur. It is one of the more frustrating errors in VBA as it can often pop up for no apparent reason when your code looks perfectly fine!

(See our Error Handling Guide for more information about VBA Errors)

Referring to a Variable no Longer Active

An Automation Error could occur when you are referring to a workbook or worksheet via a variable, but the variable is no longer active.

Sub TestAutomation()
  Dim strFile As String
  Dim wb As Workbook
'open file and set workbook variable
  strFile = Application.GetOpenFilename
  Set wb = Workbooks.Open(strFile)
'Close the workbook
  wb.Close
'try to activate the workbook
  wb.Activate
End Sub

When we run the code above, we will get an automation error.  This is due to the fact that we have opened a workbook and assigned a variable to that workbook. We have then closed the workbook but in the next line of code we try to activate the closed workbook.  This will cause the error as the variable is no longer active.

VBA AutomationError

If we want to activate a workbook, we first need to have the workbook open!

Memory Overload

This error can also sometimes occur if you have a loop and you forget to clear an object during the course of the loop. However, it might only occur sometimes, and not others-  which is one of the reasons why this error is can be so annoying.

Take for example this code below:

Sub InsertPicture()
  Dim i As Integer
  Dim shp As Object
  For i = 1 To 100
    With Worksheets("Sheet1")
'set the object variable
       Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
    End With
    With shp
     .Object.PictureSizeMode = 3
'load the picture
     .Object.Picture = LoadPicture("C:dataimage" & i & ".jpg")
     .Object.BorderStyle = 0
     .Object.BackStyle = 0
    End With
  Next i
End Sub

The variable is declared as an Object, and then the SET keyword is used to assign an image to the object. The object is then populated with an image and inserted into the Excel sheet with some formatting taking place at the same time.  We then add a loop to the code to insert 100 images into the Excel sheet. Occasionally this causes an automation error, but sometimes it doesn’t – frustrating, right?

The solution to this problem is to clear the object variable within the loop by setting the object to NOTHING – this will free the memory and prevent the error.

 Sub InsertPicture()
  Dim i As Integer
  Dim shp As Object
  For i = 1 To 100
    With Worksheets("Sheet1")
'set the object variable
     Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
    End With
    With shp
     .Object.PictureSizeMode = 3
'load the picture
     .Object.Picture = LoadPicture("C:dataimage.jpg")
     .Object.BorderStyle = 0
     .Object.BackStyle = 0
    End With
'clear the object variable
    Set shp = Nothing
  Next i
End Sub

DLL Errors and Updating Windows

Sometimes the error occurs and there is nothing that can be done within VBA code.  Re-registering DLL’s that are being used, making sure that our Windows is up to date and as a last resort, running a Registry Check as sometimes the only things that may work to clear this error.

A good way of avoiding this error is to make sure that error traps are in place using the On Error Go To or On Error Resume Next routines.

VBA Coding Made Easy

Stop searching for VBA code online. Learn more about AutoMacro — A VBA Code Builder that allows beginners to code procedures from scratch with minimal coding knowledge and with many time-saving features for all users!
vba save as

Learn More!

One of the more frustrating errors to occur in VBA is the Automation Error.  It can often pop up for no apparent reason despite your code looking perfect.

Reasons for This Error

There are a variety of reasons that this can occur.

Microsoft Office is made up of Objects – the Workbook object, Worksheet Object, Range object and Cell object to name just a few in Excel; and the Document Object in Word.  Each object has multiple properties and methods that are able to be programmed to control how the object behaves. If you do not program these methods correctly, or do not set a property correctly, then an automation error can occur.

It can be highly annoying as the code will run perfectly for a while, and then suddenly you’ll see this!

Run-time error
Automation error
Unspecified error

You may get a number of different messages for this error.

The Object Has Disconnected from Its Client

An automation error could occur when you are referring to a workbook or worksheet via a variable, but the variable is no longer active.  Make sure any object variables that you are referring to in your code are still valid when you call the property and methods that you are controlling them with.

Excel Error Load Form

An automation error could occur within Excel if you load a form while another object (like the worksheet or range object) are still referenced.  Remember to set your object references to NOTHING after you have finished writing the code to control them with.

Error Hiding/Unhiding Sheets In Excel

There are 3 ways to control the visible property in an Excel sheet in VBA – xlSheetVisible, xlSheetHidden or xlSheetVeryHidden.   An automation error could occur if you are trying to write information to a sheet which has the xlVeryHidden property set – make sure you set the sheet to visible in the code before you try to write anything to the sheet using Visual Basic Code.

Error 429 and 440

If you receive either of these errors, it can mean that your DLL files or ActiveX controls that you might be using are not correctly registered on your PC, or if you are using an API incorrectly.  It can also occur if you are running using 32-bit files on a 64-bit machine, or vice versa. 

Automation Error When Running Macro Enabled Workbook Over A Network

If you have a workbook open over a network, and you get an automation error when you run a macro, check your network connections – it could be that the network path is no longer valid.   Check you network paths and connections and make sure that they are all still working.

ADODB Automation Error

This error can occur when you are programming within Microsoft Access and are using the ADODB.Connection object.  It can be caused by any number of reasons from conflicting DLL files to a registry corruption, or simply that you did not set the recordlist object to nothing when you were finished using it!

Common Causes and Things to Check

Here are some reasons you might be getting the error. Perhaps you are…

  • Trying to write information to hidden sheets or cells.
  • Trying to write information to other documents or workbooks.
  • Referring to objects that do not exist.
  • Needing to install an update to Office, or the correct .Net framework.
  • Loading objects (like pictures) into memory using a loop, and failing to clear the memory between each load (set Pic = Nothing).
  • A Corrupt Registry – this is a hard one, as it often means that you need to remove Office entirely from your machine and then re-install it.  

Ways to Solve It

Error Trapping

Error trapping is one of the best ways to solve this problem.  You can use On Error Resume Next – or On Error GoTo Label – depending on your needs at the time.  If you want the code to carry on running and ignore the error, use On Error Resume Next.  If you want the code to stop running, create an error label and direct the code to that error label by using On Error GoTo label.

Clear the Memory

Another way to solve the problem is to make sure you clear any referred objects either in a loop or at the end of your code.  For example, if you have referred to a picture object, set the picture object to NOTHING, or if you have referred to a Worksheet object, set the Worksheet object to NOTHING once you have run the code for that picture of worksheet.

The code example below will insert a picture into a worksheet.  It may or may not give you an automation error!

Sub InsertPicture()
	Dim i As Integer
	For i = 1 To 100
		With Worksheets("Sheet1")
 		Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", _
 		Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left
		, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
 		End With
		 With shp
			.Object.PictureSizeMode = 3
			.Object.Picture = LoadPicture("C:dataimage" & i & ".jpg")
			.Object.BorderStyle = 0
			.Object.BackStyle = 0
	 End With
	Next i
End Sub

The variable is declared as an OLEObject, and then the SET keyword is used to assign an image to the object.  The object is then populated with an image and inserted into the Excel sheet – some formatting taking place at the same time. I have then added a loop to the code to insert 100 images into the Excel sheet.  Occasionally this causes an automation error, but sometimes it doesn’t – frustrating, right?

The error often occurs when Excel runs out of memory – assigning an object over and over again without clearing the object could mean that Excel is struggling with memory and could lead to an automation error.

We can solve this problem 2 ways:

  1. Set the object to NOTHING after it is inserted each time
  2. Add an error trap to the code.
Sub InsertPicture()
On Error Resume Next
	Dim i As Integer
	For i = 1 To 100
		With Worksheets("Sheet1")
 		Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", _
 		Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left
		, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
 		End With
		 With shp
			.Object.PictureSizeMode = 3
			.Object.Picture = LoadPicture("C:dataimage" & i & ".jpg")
			.Object.BorderStyle = 0
			.Object.BackStyle = 0
	 End With
	Set shp = Nothing
	Next i
End Sub

Make sure your PC is up to date

A third way to solve the problem is to install the required update to Office or Windows, or the latest version of the .Net framework.  You can check to see if there are any updates available for your PC in your ‘Check for updates’ setting on your PC.

In Windows 10, you can type ‘updates’ in the search bar, and it will enable you to click on “Check for updates“.

Check for updates in Windows 10

It is always a good idea to keep your machine up to date.

Windows 10 is up to date

Run a Registry Check

If all else fails, there are external software programs that you can download to run a check on the registry of your PC.

As you can see from above, this error often has a mind of its own – and can be very frustrating to solve.  A lot of the times trial and error is required, however, writing clean code with good error traps and referring to methods, properties and objects correctly often can solve the problem.

One of the more frustrating errors to occur in VBA is the Automation Error.  It can often pop up for no apparent reason despite your code looking perfect.

Contents

  • Reasons for This Error
    • The Object Has Disconnected from Its Client
    • Excel Error Load Form
    • Error Hiding/Unhiding Sheets In Excel
    • Error 429 and 440
    • Automation Error When Running Macro Enabled Workbook Over A Network
    • ADODB Automation Error
  • Common Causes and Things to Check
  • Ways to Solve It
    • Error Trapping
    • Clear the Memory
    • Make sure your PC is up to date
  • Run a Registry Check

Reasons for This Error

There are a variety of reasons that this can occur.

Microsoft Office is made up of Objects – the Workbook object, Worksheet Object, Range object and Cell object to name just a few in Excel; and the Document Object in Word.  Each object has multiple properties and methods that are able to be programmed to control how the object behaves. If you do not program these methods correctly, or do not set a property correctly, then an automation error can occur.

It can be highly annoying as the code will run perfectly for a while, and then suddenly you’ll see this!

Run-time error Automation error Unspecified error

You may get a number of different messages for this error.

The Object Has Disconnected from Its Client

An automation error could occur when you are referring to a workbook or worksheet via a variable, but the variable is no longer active.  Make sure any object variables that you are referring to in your code are still valid when you call the property and methods that you are controlling them with.

Excel Error Load Form

An automation error could occur within Excel if you load a form while another object (like the worksheet or range object) are still referenced.  Remember to set your object references to NOTHING after you have finished writing the code to control them with.

Error Hiding/Unhiding Sheets In Excel

There are 3 ways to control the visible property in an Excel sheet in VBA – xlSheetVisible, xlSheetHidden or xlSheetVeryHidden.   An automation error could occur if you are trying to write information to a sheet which has the xlVeryHidden property set – make sure you set the sheet to visible in the code before you try to write anything to the sheet using Visual Basic Code.

Error 429 and 440

If you receive either of these errors, it can mean that your DLL files or ActiveX controls that you might be using are not correctly registered on your PC, or if you are using an API incorrectly.  It can also occur if you are running using 32-bit files on a 64-bit machine, or vice versa. 

Automation Error When Running Macro Enabled Workbook Over A Network

If you have a workbook open over a network, and you get an automation error when you run a macro, check your network connections – it could be that the network path is no longer valid.   Check you network paths and connections and make sure that they are all still working.

ADODB Automation Error

This error can occur when you are programming within Microsoft Access and are using the ADODB.Connection object.  It can be caused by any number of reasons from conflicting DLL files to a registry corruption, or simply that you did not set the recordlist object to nothing when you were finished using it!

Common Causes and Things to Check

Here are some reasons you might be getting the error. Perhaps you are…

  • Trying to write information to hidden sheets or cells.
  • Trying to write information to other documents or workbooks.
  • Referring to objects that do not exist.
  • Needing to install an update to Office, or the correct .Net framework.
  • Loading objects (like pictures) into memory using a loop, and failing to clear the memory between each load (set Pic = Nothing).
  • A Corrupt Registry – this is a hard one, as it often means that you need to remove Office entirely from your machine and then re-install it.  

Ways to Solve It

Error Trapping

Error trapping is one of the best ways to solve this problem.  You can use On Error Resume Next – or On Error GoTo Label – depending on your needs at the time.  If you want the code to carry on running and ignore the error, use On Error Resume Next.  If you want the code to stop running, create an error label and direct the code to that error label by using On Error GoTo label.

Clear the Memory

Another way to solve the problem is to make sure you clear any referred objects either in a loop or at the end of your code.  For example, if you have referred to a picture object, set the picture object to NOTHING, or if you have referred to a Worksheet object, set the Worksheet object to NOTHING once you have run the code for that picture of worksheet.

The code example below will insert a picture into a worksheet.  It may or may not give you an automation error!

Sub InsertPicture()
	Dim i As Integer
	For i = 1 To 100
		With Worksheets("Sheet1")
 		Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", _
 		Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left
		, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
 		End With
		 With shp
			.Object.PictureSizeMode = 3
			.Object.Picture = LoadPicture("C:dataimage" & i & ".jpg")
			.Object.BorderStyle = 0
			.Object.BackStyle = 0
	 End With
	Next i
End Sub

The variable is declared as an OLEObject, and then the SET keyword is used to assign an image to the object.  The object is then populated with an image and inserted into the Excel sheet – some formatting taking place at the same time. I have then added a loop to the code to insert 100 images into the Excel sheet.  Occasionally this causes an automation error, but sometimes it doesn’t – frustrating, right?

The error often occurs when Excel runs out of memory – assigning an object over and over again without clearing the object could mean that Excel is struggling with memory and could lead to an automation error.

We can solve this problem 2 ways:

  1. Set the object to NOTHING after it is inserted each time
  2. Add an error trap to the code.
Sub InsertPicture()
On Error Resume Next
	Dim i As Integer
	For i = 1 To 100
		With Worksheets("Sheet1")
 		Set shp = .OLEObjects.Add(ClassType:="Forms.Image.1", _
 		Link:=False, DisplayAsIcon:=False, Left:=.Cells(i, "A").Left
		, Top:=.Cells(i, "A").Top, Width:=264, Height:=124)
 		End With
		 With shp
			.Object.PictureSizeMode = 3
			.Object.Picture = LoadPicture("C:dataimage" & i & ".jpg")
			.Object.BorderStyle = 0
			.Object.BackStyle = 0
	 End With
	Set shp = Nothing
	Next i
End Sub

Make sure your PC is up to date

A third way to solve the problem is to install the required update to Office or Windows, or the latest version of the .Net framework.  You can check to see if there are any updates available for your PC in your ‘Check for updates’ setting on your PC.

In Windows 10, you can type ‘updates’ in the search bar, and it will enable you to click on “Check for updates“.

Check for updates in Windows 10

It is always a good idea to keep your machine up to date.

Windows 10 is up to date

Run a Registry Check

If all else fails, there are external software programs that you can download to run a check on the registry of your PC.

As you can see from above, this error often has a mind of its own – and can be very frustrating to solve.  A lot of the times trial and error is required, however, writing clean code with good error traps and referring to methods, properties and objects correctly often can solve the problem.

Содержание

  1. VBA Automation Error
  2. Referring to a Variable no Longer Active
  3. Memory Overload
  4. DLL Errors and Updating Windows
  5. VBA Coding Made Easy
  6. VBA Code Examples Add-in
  7. VBA On Error – Error Handling Best Practices
  8. VBA Errors Cheat Sheet
  9. Errors
  10. VBA Error Handling
  11. VBA On Error Statement
  12. On Error GoTo 0
  13. On Error Resume Next
  14. VBA Coding Made Easy
  15. Err.Number, Err.Clear, and Catching Errors
  16. Error Handling with Err.Number
  17. On Error GoTo Line
  18. On Error Exit Sub
  19. Err.Clear, On Error GoTo -1, and Resetting Err.Number
  20. VBA On Error MsgBox
  21. VBA IsError
  22. If Error VBA
  23. VBA Error Types
  24. Runtime Errors
  25. Syntax Errors
  26. Compile Errors
  27. Debug > Compile
  28. OverFlow Error
  29. Other VBA Error Terms
  30. VBA Catch Error
  31. VBA Ignore Error
  32. VBA Throw Error / Err.Raise
  33. VBA Error Trapping
  34. VBA Error Message
  35. VBA Error Handling in a Loop
  36. VBA Error Handling in Access
  37. VBA Code Examples Add-in

In this Article

This tutorial will explain what a VBA Automation Error means and how it occurs.

Excel is made up of objects – the Workbook object, Worksheet object, Range object and Cell object to name but a few. Each object has multiple properties and methods whose behavior can be controlled with VBA code. If the VBA code is not correctly programmed, then an automation error can occur. It is one of the more frustrating errors in VBA as it can often pop up for no apparent reason when your code looks perfectly fine!

(See our Error Handling Guide for more information about VBA Errors)

Referring to a Variable no Longer Active

An Automation Error could occur when you are referring to a workbook or worksheet via a variable, but the variable is no longer active.

When we run the code above, we will get an automation error. This is due to the fact that we have opened a workbook and assigned a variable to that workbook. We have then closed the workbook but in the next line of code we try to activate the closed workbook. This will cause the error as the variable is no longer active.

If we want to activate a workbook, we first need to have the workbook open!

Memory Overload

This error can also sometimes occur if you have a loop and you forget to clear an object during the course of the loop. However, it might only occur sometimes, and not others- which is one of the reasons why this error is can be so annoying.

Take for example this code below:

The variable is declared as an Object, and then the SET keyword is used to assign an image to the object. The object is then populated with an image and inserted into the Excel sheet with some formatting taking place at the same time. We then add a loop to the code to insert 100 images into the Excel sheet. Occasionally this causes an automation error, but sometimes it doesn’t – frustrating, right?

The solution to this problem is to clear the object variable within the loop by setting the object to NOTHING – this will free the memory and prevent the error.

DLL Errors and Updating Windows

Sometimes the error occurs and there is nothing that can be done within VBA code. Re-registering DLL’s that are being used, making sure that our Windows is up to date and as a last resort, running a Registry Check as sometimes the only things that may work to clear this error.

A good way of avoiding this error is to make sure that error traps are in place using the On Error Go To or On Error Resume Next routines.

VBA Coding Made Easy

Stop searching for VBA code online. Learn more about AutoMacro — A VBA Code Builder that allows beginners to code procedures from scratch with minimal coding knowledge and with many time-saving features for all users!

VBA Code Examples Add-in

Easily access all of the code examples found on our site.

Simply navigate to the menu, click, and the code will be inserted directly into your module. .xlam add-in.

Источник

VBA On Error – Error Handling Best Practices

In this Article

VBA Errors Cheat Sheet

Errors

VBA Error Handling

VBA Error Handling refers to the process of anticipating, detecting, and resolving VBA Runtime Errors. The VBA Error Handling process occurs when writing code, before any errors actually occur.

VBA Runtime Errors are errors that occur during code execution. Examples of runtime errors include:

  • Referencing a non-existent workbook, worksheet, or other object (Run-time Error 1004)
  • Invalid data ex. referencing an Excel cell containing an error (Type Mismatch – Run-time Error 13)
  • Attempting to divide by zero

VBA On Error Statement

Most VBA error handling is done with the On Error Statement. The On Error statement tells VBA what to do if it encounters an error. There are three On Error Statements:

  • On Error GoTo 0
  • On Error Resume Next
  • On Error GoTo Line

On Error GoTo 0

On Error GoTo 0 is VBA’s default setting. You can restore this default setting by adding the following line of code:

When an error occurs with On Error GoTo 0, VBA will stop executing code and display its standard error message box.

Often you will add an On Error GoTo 0 after adding On Error Resume Next error handling (next section):

On Error Resume Next

On Error Resume Next tells VBA to skip any lines of code containing errors and proceed to the next line.

Note: On Error Resume Next does not fix an error, or otherwise resolve it. It simply tells VBA to proceed as if the line of code containing the error did not exist. Improper use of On Error Resume Next can result in unintended consequences.

A great time to use On Error Resume Next is when working with objects that may or may not exist. For example, you want to write some code that will delete a shape, but if you run the code when the shape is already deleted, VBA will throw an error. Instead you can use On Error Resume Next to tell VBA to delete the shape if it exists.

Notice we added On Error GoTo 0 after the line of code containing the potential error. This resets the error handling.

In the next section we’ll show you how to test if an error occurred using Err.Number, giving you more advanced error handling options.

VBA Coding Made Easy

Stop searching for VBA code online. Learn more about AutoMacro — A VBA Code Builder that allows beginners to code procedures from scratch with minimal coding knowledge and with many time-saving features for all users!

Err.Number, Err.Clear, and Catching Errors

Instead of simply skipping over a line containing an error, we can catch the error by using On Error Resume Next and Err.Number.

Err.Number returns an error number corresponding with the type of error detected. If there is no error, Err.Number = 0.

For example, this procedure will return “11” because the error that occurs is Run-time error ’11’.

Error Handling with Err.Number

The true power of Err.Number lies in the ability to detect if an error occurred (Err.Number <> 0). In the example below, we’ve created a function that will test if a sheet exists by using Err.Number.

Note: We’ve added a On Error GoTo -1 to the end which resets Err.Number to 0 (see two sections down).

With On Error Resume Next and Err.Number, you can replicate the “Try” & “Catch” functionality of other programming languages.

On Error GoTo Line

On Error GoTo Line tells VBA to “go to” a labeled line of code when an error is encountered. You declare the Go To statement like this (where errHandler is the line label to go to):

and create a line label like this:

Note: This is the same label that you’d use with a regular VBA GoTo Statement.

Below we will demonstrate using On Error GoTo Line to Exit a procedure.

On Error Exit Sub

You can do this by placing the error handler line label at the end of your procedure:

Err.Clear, On Error GoTo -1, and Resetting Err.Number

After an error is handled, you should generally clear the error to prevent future issues with error handling.

After an error occurs, both Err.Clear and On Error GoTo -1 can be used to reset Err.Number to 0. But there is one very important difference: Err.Clear does not reset the actual error itself, it only resets the Err.Number.

What does that mean? Using Err.Clear, you will not be able to change the error handling setting. To see the difference, test out this code and replace On Error GoTo -1 with Err.Clear:

Typically, I recommend always using On Error GoTo -1, unless you have a good reason to use Err.Clear instead.

VBA On Error MsgBox

You might also want to display a Message Box on error. This example will display different message boxes depending on where the error occurs:

Here you would replace Err.Raise(11) with your actual code.

VBA IsError

Another way to handle errors is to test for them with the VBA ISERROR Function. The ISERROR Function tests an expression for errors, returning TRUE or FALSE if an error occurs.

If Error VBA

You can also handle errors in VBA with the Excel IFERROR Function. The IFERROR Function must be accessed by using the WorksheetFunction Class:

This will output the value of Range A10, if the value is an error, it will output 0 instead.

VBA Error Types

Runtime Errors

As stated above:

VBA Runtime Errors are errors that occur during code execution. Examples of runtime errors include:

  • Referencing a non-existent workbook, worksheet, or other object
  • Invalid data ex. referencing an Excel cell containing an error
  • Attempting to divide by zero

You can “error handle” runtime errors using the methods discussed above.

Syntax Errors

VBA Syntax Errors are errors with code writing. Examples of syntax errors include:

  • Mispelling
  • Missing or incorrect punctuation

The VBA Editor identifies many syntax errors with red highlighting:

The VBA Editor also has an option to “Auto Syntax Check”:

When this is checked, the VBA Editor will generate a message box alerting you syntax errors after you enter a line of code:

I personally find this extremely annoying and disable the feature.

Compile Errors

Before attempting to run a procedure, VBA will “compile” the procedure. Compiling transforms the program from source code (that you can see) into executable form (you can’t see).

VBA Compile Errors are errors that prevent the code from compiling.

A good example of a compile error is a missing variable declaration:

Other examples include:

  • For without Next
  • Select without End Select
  • If without End If
  • Calling a procedure that does not exist

Syntax Errors (previous section) are a subset of Compile Errors.

Debug > Compile

Compile errors will appear when you attempt to run a Procedure. But ideally, you would identify compile errors prior to attempting to run the procedure.

You can do this by compiling the project ahead of time. To do so, go to Debug > Compile VBA Project.

The compiler will “go to” the first error. Once you fix that error, compile the project again. Repeat until all errors are fixed.

You can tell that all errors are fixed because Compile VBA Project will be grayed out:

OverFlow Error

The VBA OverFlow Error occurs when you attempt to put a value into a variable that is too large. For example, Integer Variables can only contain values between -32,768 to 32,768. If you enter a larger value, you’ll receive an Overflow error:

Instead, you should use the Long Variable to store the larger number.

Other VBA Error Terms

VBA Catch Error

Unlike other programming languages, In VBA there is no Catch Statement. However, you can replicate a Catch Statement by using On Error Resume Next and If Err.Number <> 0 Then. This is covered above in Error Handling with Err.Number.

VBA Ignore Error

To ignore errors in VBA, simply use the On Error Resume Next statement:

However, as mentioned above, you should be careful using this statement as it doesn’t fix an error, it just simply ignores the line of code containing the error.

VBA Throw Error / Err.Raise

To through an error in VBA, you use the Err.Raise method.

This line of code will raise Run-time error ’13’: Type mismatch:

VBA Error Trapping

VBA Error Trapping is just another term for VBA Error Handling.

VBA Error Message

A VBA Error Message looks like this:

When you click ‘Debug’, you’ll see the line of code that is throwing the error:

VBA Error Handling in a Loop

The best way to error handle within a Loop is by using On Error Resume Next along with Err.Number to detect if an error has occurred (Remember to use Err.Clear to clear the error after each occurrence).

The example below will divide two numbers (Column A by Column B) and output the result into Column C. If there’s an error, the result will be 0.

VBA Error Handling in Access

All of the above examples work exactly the same in Access VBA as in Excel VBA.

VBA Code Examples Add-in

Easily access all of the code examples found on our site.

Simply navigate to the menu, click, and the code will be inserted directly into your module. .xlam add-in.

Источник

“Abort, Retry, Fail?” – MS-DOS error message circa 1986

This post provides a complete guide to VBA Error Handing. If you are looking for a quick summary then check out the quick guide table in the first section.

If you are looking for a particular topic on VBA Error Handing then check out the table of contents below(if it’s not visible click on the post header).

If you are new to VBA Error Handling, then you can read the post from start to finish as it is laid out in logical order.

Contents

  • 1 A Quick Guide to Error Handing
  • 2 The Webinar
  • 3 Download the Error Handling Library
  • 4 Introduction
  • 5 VBA Errors
    • 5.1 Syntax Errors
    • 5.2 Compilation Errors
      • 5.2.1 Using Debug->Compile
      • 5.2.2 Debug->Compile Error Summary
      • 5.2.3 Debug->Compile Usage
    • 5.3 Runtime Errors
      • 5.3.1 Expected Versus Unexpected Errors
    • 5.4 Runtime Errors that are not VBA Errors
  • 6 The On Error Statement
    • 6.1 On Error GoTo 0
    • 6.2 On Error Resume Next
    • 6.3 On Error GoTo [label]
    • 6.4 On Error GoTo -1
    • 6.5 Using On Error
  • 7 Resume Next
  • 8 The Err Object
    • 8.1 Getting the Line Number
    • 8.2 Using Err.Raise
    • 8.3 Using Err.Clear
  • 9 Logging
  • 10 Other Error Related Items
    • 10.1 Error Function
    • 10.2 Error Statement
  • 11 A Simple Error Handling Strategy
    • 11.1 The Basic Implementation
  • 12 A Complete Error Handling Strategy
    • 12.1 An Example of using this strategy
  • 13 Error Handling in a Nutshell
  • 14 What’s Next?

A Quick Guide to Error Handing

Item Description
On Error Goto 0 When error occurs, the code stops and displays the error.
On Error Goto -1 Clears the current error setting and reverts to the default.
On Error Resume Next Ignores the error and continues on.
On Error Goto [Label] Goes to a specific label when an error occurs.
This allows us to handle the error.
Err Object When an error occurs the error information is stored here.
Err.Number The number of the error.
(Only useful if you need to check a specific error occurred.)
Err.Description Contains the error text.
Err.Source You can populate this when you use Err.Raise.
Err.Raise A function that allows you to generate your own error.
Error Function Returns the error text from an error number.
Obsolete.
Error Statement Simulates an error. Use Err.Raise instead.

The Webinar

Members of the Webinar Archives can access the webinar for this article by clicking on the image below.

(Note: Archive members have access to the webinar archive.)

vba error handling video

Download the Error Handling Library

Introduction

Error Handling refers to code that is written to handle errors which occur when your application is running. These errors are normally caused by something outside your control like a missing file, database being unavailable, data being invalid etc.

If we think an error is likely to occur at some point, it is good practice to write specific code to handle the error if it occurs and deal with it.

For all other errors, we use generic code to deal with them. This is where the VBA error handling statement comes into play. They allow our application to deal gracefully with any errors we weren’t expecting.

To understand error handling we must first understand the different types of errors in VBA.

VBA Error Handling

VBA Errors

There are three types of errors in VBA:

  1. Syntax
  2. Compilation
  3. Runtime

We use error handling to deal with runtime errors. Let’s have a look at each of these error types so that it is clear what a runtime error is.

Syntax Errors

If you have used VBA for any length of time you will have seen a syntax error. When you type a line and press return, VBA will evaluate the syntax and if it is not correct it will display an error message.

For example if you type If and forget the Then keyword, VBA will display the following error message

VBA Error Handling

Some examples of syntax errors are

' then is missing
If a > b

' equals is missing after i
For i 2 To 7

' missing right parenthesis
b = left("ABCD",1

Syntax errors relate to one line only. They occur when the syntax of one line is incorrect.

Note: You can turn off the Syntax error dialog by going to Tools->Options and checking off “Auto Syntax Check”. The line will still appear red if there is an error but the dialog will not appear.

Compilation Errors

Compilation errors occur over more than one line. The syntax is correct on a single line but is incorrect when all the project code is taken into account.

Examples of compilation errors are:

  • If statement without corresponding End If statement
  • For without Next
  • Select without End Select
  • Calling a Sub or Function that does not exist
  • Calling a Sub or Function with the wrong parameters
  • Giving a Sub or Function the same name as a module
  • Variables not declared(Option Explicit must be present at the top of the module)

The following screenshot shows a compilation error that occurs when a For loop has no matching Next statement.

VBA Error Handling

Using Debug->Compile

To find compilation errors, we use Debug->Compile VBA Project from the Visual Basic menu.

When you select Debug->Compile, VBA displays the first error it comes across.

When this error is fixed, you can run Compile again and VBA will then find the next error.

Debug->Compile will also include syntax errors in it’s search which is very useful.

If there are no errors left and you run Debug->Compile , it may appear that nothing happened. However, “Compile” will be grayed out in the Debug menu. This means your application has no compilation errors at the current time.

Debug->Compile Error Summary

  • Debug->Compile finds compilation(project wide) errors.
  • It will also find syntax errors.
  • It finds one error each time you use it.
  • When there are no compilation errors left the Compile option will appear grayed out in the menu.

Debug->Compile Usage

You should always use Debug->Compile before you run your code. This ensures that your code has no compilation errors when you run it.

If you do not run Debug->Compile then VBA may find compile errors when it runs. These should not be confused with Runtime errors.

Runtime Errors

Runtime errors occur when your application is running. They are normally outside of your control but can be caused by errors in your code.

VBA Error Handling

For example, imagine your application reads from an external workbook. If this file gets deleted then VBA will display an error when your code tries to open it.

Other examples of runtime errors are

  • a database not being available
  • the user entering invalid data
  • a cell containing text instead of a number

As we have seen, the purpose of error handling is to deal with runtime errors when they occur.

Expected Versus Unexpected Errors

When we think a runtime error could occur we put code in place to handle it. For example, we would normally put code in place to deal with a file not being found.

The following code checks if the file exists before it tries to open it. If the file does not exist then a user friendly message is displayed and the code exits the sub.

' https://excelmacromastery.com/
Sub OpenFile()
    
    Dim sFile As String
    sFile = "C:docsdata.xlsx"
    
    ' Use Dir to check if file exists
    If Dir(sFile) = "" Then
        ' if file does not exist display message
        MsgBox "Could not find the file " & sFile
        Exit Sub
    End If
    
    ' Code will only reach here if file exists
    Workbooks.Open sFile
    
End Sub

When we think an error is likely to occur at some point, it is good practice to add code to handle the situation. We normally refer to these errors as expected errors.

If we don’t have specific code to handle an error it is considered an unexpected error. We use the VBA error handling statements to handle the unexpected errors.

Runtime Errors that are not VBA Errors

Before we look at the VBA Handling there is one type of error we must mention. Some runtime errors are not considered errors by VBA but only by the user.

Let me explain this with an example. Imagine you have an application that requires you to add the values in the variables a and b

result = a + b

Let’s say you mistakenly use an asterisk instead of the plus sign

result = a * b

This is not a VBA error. Your code syntax is perfectly legal. However, from your requirements point of view it is an error.

These errors cannot be dealt with using error handling as they obviously won’t generate any error. You can deal with these errors using Unit Testing and Assertions. I have an in-depth post about using VBA assertions – see How to Make Your Code BulletProof.

The On Error Statement

As we have seen there are two ways to treat runtime errors

  1. Expected errors – write specific code to handle them.
  2. Unexpected errors – use VBA error handling statements to handle them.

The VBA On Error statement is used for error handling. This statement performs some action when an error occurs during runtime.

There are four different ways to use this statement

  1. On Error GoTo 0 – the code stops at the line with the error and displays a message.
  2. On Error Resume Next – the code moves to next line. No error message is displayed.
  3. On Error GoTo [label] – the code moves to a specific line or label. No error message is displayed. This is the one we use for error handling.
  4. On Error GoTo -1 – clears the current error.

Let’s look at each of these statements in turn.

On Error GoTo 0

This is the default behavior of VBA. In other words, if you don’t use On Error then this is the behavior you will see.

When an error occurs, VBA stops on the line with the error and displays the error message. The application requires user intervention with the code before it can continue. This could be fixing the error or restarting the application. In this scenario no error handling takes place.

Let’s look at an example. In the following code, we have not used any On Error line so VBA will use the On Error GoTo 0 behavior by default.

' https://excelmacromastery.com/
Sub UsingDefault()

    Dim x As Long, y As Long
    
    x = 6
    y = 6 / 0
    x = 7

End Sub

The second assignment line results in a divide by zero error. When we run this code we will get the error message shown in the screenshot below

VBA Error Handling

When the error appears you can choose End or Debug

If you select End then the application simply stops.
If you select Debug the application stops on the error line as the screenshot below shows

VBA Error Handling

This behaviour is fine when you are writing VBA code as it shows you the exact line with the error.

This behavior is unsuitable for an application that you are given to a user. These errors look unprofessional and they make the application look unstable.

An error like this is essentially the application crashing. The user cannot continue on without restarting the application. They may not use it at all until you fix the error for them.

By using On Error GoTo [label] we can give the user a more controlled error message. It also prevents the application stopping. We can get the application to perform in a predefined manner.

On Error Resume Next

Using On Error Resume Next tells VBA to ignore the error and continue on.

There are specific occasions when this is useful. Most of the time you should avoid using it.

If we add Resume Next to our example Sub then VBA will ignore the divide by zero error

' https://excelmacromastery.com/
Sub UsingResumeNext()

    On Error Resume Next
    
    Dim x As Long, y As Long
    
    x = 6
    y = 6 / 0
    x = 7

End Sub

It is not a good idea to do this. If you ignore the error, then the behavior can be unpredictable. The error can affect the application in multiple ways.You could end up with invalid data. The problem is that you aren’t aware that something went wrong because you have suppressed the error.

The code below is an example of where using Resume Next is valid

' https://excelmacromastery.com/
Sub SendMail()

   On Error Resume Next
   
    ' Requires Reference:
    ' Microsoft Outlook 15.0 Object Library
    Dim Outlook As Outlook.Application
    Set Outlook = New Outlook.Application

    If Outlook Is Nothing Then
        MsgBox "Cannot create Microsoft Outlook session." _
                   & " The email will not be sent."
        Exit Sub
    End If
    
End Sub

In this code we are checking to see if Microsoft Outlook is available on a computer. All we want to know is if it is available or not. We are not interested in the specific error.

In the code above, we continue on if there is an error. Then in the next line we check the value of the Outlook variable. If there has been an error then the value of this variable will be set to Nothing.

This is an example of when Resume could be useful. The point is that even though we use Resume we are still checking for the error. The vast majority of the time you will not need to use Resume.

On Error GoTo [label]

This is how we use Error Handling in VBA. It is the equivalent of the Try and Catch functionality you see in languages such as C# and Java.

When an error occurs you send the error to a specific label. It is normally at the bottom of the sub.

Let’s apply this to the sub we have been using

' https://excelmacromastery.com/
Sub UsingGotoLine()

    On Error GoTo eh
    
    Dim x As Long, y As Long
    
    x = 6
    y = 6 / 0
    x = 7
    
Done:
    Exit Sub
eh:
    MsgBox "The following error occurred: " & Err.Description
End Sub

The screenshot below shows what happens when an error occurs

VBA Error Handling

VBA jumps to the eh label because we specified this in the On Error Goto line.

Note 1: The label we use in the On…GoTo statement, must be in the current Sub/Function. If not you will get a compilation error.

Note 2: When an error occurs when using On Error GoTo [label], the error handling returns to the default behaviour i.e. The code will stop on the line with the error and display the error message. See the next section for more information about this.

On Error GoTo -1

This statement is different than the other three. It is used to clear the current error rather than setting a particular behaviour.

When an error occurs using On Error GoTo [label], the error handling behaviour returns to the default behaviour i.e. “On Error GoTo 0”. That means that if another error occurs the code will stop on the current line.

This behaviour only applies to the current sub. Once we exit the sub, the error will be cleared automatically.

Take a look at the code below. The first error will cause the code to jump to the eh label. The second error will stop on the line with the 1034 error.

' https://excelmacromastery.com/
Sub TwoErrors()

    On Error Goto eh
        
    ' generate "Type mismatch" error
    Error (13)

Done:
    Exit Sub
eh:
    ' generate "Application-defined" error
    Error (1034)
End Sub

If we add further error handling it will not work as the error trap has not been cleared.

In the code below we have added the line

On Error Goto eh_other

after we catch the first error.

This has no effect as the error has not been cleared. In other words the code will stop on the line with the error and display the message.

' https://excelmacromastery.com/
Sub TwoErrors()

    On Error Goto eh
        
    ' generate "Type mismatch" error
    Error (13)

Done:
    Exit Sub
eh:
    On Error Goto eh_other
    ' generate "Application-defined" error
    Error (1034)
Exit Sub
eh_other:
    Debug.Print "eh_other " & Err.Description
End Sub

To clear the error we use On Error GoTo -1. Think of it like setting a mouse trap. When the trap goes off you need to set it again.

In the code below we add this line and the second error will now cause the code to jump to the eh_other label

' https://excelmacromastery.com/
Sub TwoErrors()

    On Error Goto eh
        
    ' generate "Type mismatch" error
    Error (13)

Done:
    Exit Sub
eh:
    ' clear error
    On Error Goto -1
    
    On Error Goto eh_other
    ' generate "Application-defined" error
    Error (1034)
Exit Sub
eh_other:
    Debug.Print "eh_other " & Err.Description
End Sub

Note 1: There are probably rare cases where using On Error GoTo -1 is useful. In most cases using Resume Next is better as it clears the error and resumes the code at the next line after the error occurs.

Note 2: The Err Object has a member Clear. Using Clear clears the text and numbers in the Err object, but it does NOT reset the error.

Using On Error

As we have seen, VBA will do one of three things when an error occurs

  • Stop and display the error.
  • Ignore the error and continue on.
  • Jump to a specific line.

VBA will always be set to one of these behaviors. When you use On Error, VBA will change to the behaviour you specify and forget about any previous behavior.

In the following Sub, VBA changes the error behaviour each time we use the On Error statement

' https://excelmacromastery.com/
Sub ErrorStates()

    Dim x As Long
    
    ' Go to eh label if error
    On Error Goto eh
    
    ' this will ignore the error on the following line
    On Error Resume Next
    x = 1 / 0
    
    ' this will display an error message on the following line
    On Error Goto 0
    x = 1 / 0
  
Done:  
   Exit Sub
eh:
    Debug.Print Err.Description
End Sub

Resume Next

The Resume Next statement is used to clear the error and then resume the code from the line after where the error occurred.

If your code can have multiple errors and you want to keep detecting them then this line is very useful.

For example, in the following code we want to resume the code after the error has been reported:

Private Sub Main()

    On Error Goto eh
    
    Dim i As Long
    For i = 1 To 3
        ' Generate type mismatch error
         Error 13
    Next i

done:
    Exit Sub
eh:
    Debug.Print i, Err.Description
End Sub

 
We could use On Error Goto -1 to clear the code and then use a goto statement to go back to the code like this:

Private Sub Main()

    On Error Goto eh
    
    Dim i As Long
    For i = 1 To 3
        ' Generate type mismatch error
         Error 13
continue:
    Next i

done:
    Exit Sub
eh:
    Debug.Print i, Err.Description
    On Error Goto -1 ' clear the error
    Goto continue ' return to the code
End Sub

 
The Resume Next provides a nicer way of doing it and it always means the code is much clearer and easier to understand:

Private Sub Main()

    On Error Goto eh
    
    Dim i As Long
    For i = 1 To 3
        ' Generate type mismatch error
         Error 13
continue:
    Next i

done:
    Exit Sub
eh:
    Debug.Print i, Err.Description
    ' clear the error and return to the code
    Resume Next  
End Sub

The Err Object

When an error occurs you can view details of the error using the Err object.

When an runtime error occurs, VBA automatically fills the Err object with details.

The code below will print “Error Number: 13 Type Mismatch” which occurs when we try to place a string value in the long integer total

' https://excelmacromastery.com/
Sub UsingErr()

    On Error Goto eh
    
    Dim total As Long
    total = "aa"

Done:
    Exit Sub
eh:
    Debug.Print "Error number: " & Err.Number _
            & " " & Err.Description
End Sub

The Err.Description provides details of the error that occurs. This is the text you normally see when an error occurs e.g. “Type Mismatch”

The Err.Number is the ID number of the error e.g. the error number for “Type Mismatch” is 13. The only time you really need this is if you are checking that a specific error occurred and this is only necessary on rare occasions.

The Err.Source property seems like a great idea but it does not work for a VBA error. The source will return the project name, which hardly narrows down where the error occurred. However, if you create an error using Err.Raise you can set the source yourself and this can be very useful.

Getting the Line Number

The Erl function is used to return the line number where the error occurs.

It often causes confusion. In the following code, Erl will return zero

' https://excelmacromastery.com/
Sub UsingErr()

    On Error Goto eh
    
    Dim val As Long
    val = "aa"

Done:
    Exit Sub
eh:
    Debug.Print Erl
End Sub

This is because there are no line numbers present. Most people don’t realise it but VBA allows you to have line numbers.

If we change the Sub above to have line number it will now print out 20

' https://excelmacromastery.com/
Sub UsingErr()

10        On Error Goto eh
          
          Dim val As Long
20        val = "aa"

Done:
30        Exit Sub
eh:
40        Debug.Print Erl
End Sub

Adding line numbers to your code manually is cumbersome. However there are tools available that will allow you to easily add and remove line numbers to a sub.

When you are finished working on a project and hand it over to the user it can be useful to add line numbers at this point. If you use the error handling strategy in the last section of this post, then VBA will report the line where the error occurred.

Using Err.Raise

Err.Raise allows us to create errors. We can use it to create custom errors for our application which is very useful. It is the equivalent of the Throw statement in JavaC#.

The format is as follows

Err.Raise [error number], [error source], [error description]

Let’s look at a simple example. Imagine we want to ensure that a cell has an entry that has a length of 5 characters. We could have a specific message for this

' https://excelmacromastery.com/
Public Const ERROR_INVALID_DATA As Long = vbObjectError + 513

Sub ReadWorksheet()

    On Error Goto eh
    
    If Len(Sheet1.Range("A1")) <> 5 Then
        Err.Raise ERROR_INVALID_DATA, "ReadWorksheet" _
            , "The value in the cell A1 must have exactly 5 characters."
    End If
    
    ' continue on if cell has valid data
    Dim id As String
    id = Sheet1.Range("A1")
    

Done:
    Exit Sub
eh:
    ' Err.Raise will send code to here
    MsgBox "Error found: " & Err.Description
End Sub

When we create an error using Err.Raise we need to give it a number. We can use any number from 513 to 65535 for our error. We must use vbObjectError with the number e.g.

Err.Raise vbObjectError + 513

Using Err.Clear

Err.Clear is used to clear the text and numbers from the Err.Object. In other words, it clears the description and number.If you want the clear the actual error you can use either On Error GoTo -1 or Resume Next

It is rare that you will need to use Err.Clear but let’s have a look at an example where you might.

In the code below we are counting the number of errors that will occur. To keep it simple we are generating an error for each odd number.

We check the error number each time we go through the loop. If the number does not equal zero then an error has occurred. Once we count the error we need to set the error number back to zero so it is ready to check for the next error.

' https://excelmacromastery.com/
Sub UsingErrClear()

    Dim count As Long, i As Long

    ' Continue if error as we will check the error number
    On Error Resume Next
    
    For i = 0 To 9
        ' generate error for every second one
        If i Mod 2 = 0 Then Error (13)
        
        ' Check for error
        If Err.Number <> 0 Then
            count = count + 1
            Err.Clear    ' Clear Err once it is counted
        End If
    Next

    Debug.Print "The number of errors was: " & count
End Sub

Note 1: Err.Clear resets the text and numbers in the error object but it does not clear the error – see Resume Next Or On Error GoTo -1 for more information about clearing the actual error.

Logging

Logging means writing information from your application when it is running. When an error occurs you can write the details to a text file so you have a record of the error.

The code below shows a very simple logging procedure

' https://excelmacromastery.com/
Sub Logger(sType As String, sSource As String, sDetails As String)
    
    Dim sFilename As String
    sFilename = "C:templogging.txt"
    
    ' Archive file at certain size
    If FileLen(sFilename) > 20000 Then
        FileCopy sFilename _
            , Replace(sFilename, ".txt", Format(Now, "ddmmyyyy hhmmss.txt"))
        Kill sFilename
    End If
    
    ' Open the file to write
    Dim filenumber As Variant
    filenumber = FreeFile 
    Open sFilename For Append As #filenumber
    
    Print #filenumber, CStr(Now) & "," & sType & "," & sSource _
                                & "," & sDetails & "," & Application.UserName
    
    Close #filenumber
    
End Sub

You can use it like this

' Create unique error number
' https://excelmacromastery.com/
Public Const ERROR_DATA_MISSING As Long = vbObjectError + 514

Sub CreateReport()

    On Error Goto eh
    
    If Sheet1.Range("A1") = "" Then
       Err.Raise ERROR_DATA_MISSING, "CreateReport", "Data is missing from Cell A1"
    End If

    ' other code here
Done:
    Exit Sub
eh:
    Logger "Error", Err.Source, Err.Description
End Sub

The log is not only for recording errors. You can record other information as the application runs. When an error occurs you can then check the sequence of events before an error occurred.

Below is an example of logging. How you implement logging really depends on the nature of the application and how useful it will be:

' https://excelmacromastery.com/
Sub ReadingData()
    
    Logger "Information", "ReadingData()", "Starting to read data."
       
    Dim coll As New Collection
    ' add data to the collection
    coll.Add "Apple"
    coll.Add "Pear"
    
    If coll.Count < 3 Then
        Logger "Warning", "ReadingData()", "Number of data items is low."
    End If
    Logger "Information", "ReadingData()", "Number of data items is " & coll.Count
    
    Logger "Information", "ReadingData()", "Finished reading data."

End Sub

Having a lot of information when dealing with an error can be very useful. Often the user may not give you accurate information about the error that occurred. By looking at the log you can get more accurate information about the information.

This section covers some of the other Error Handling tools that VBA has. These items are considered obsolete but I have included them as they may exist in legacy code.

Error Function

The Error Function is used to print the error description from a given error number. It is included in VBA for backward compatibility and is not needed because you can use the Err.Description instead.

Below are some examples:

' Print the text "Division by zero"
Debug.Print Error(11)
' Print the text "Type mismatch"
Debug.Print Error(13)
' Print the text "File not found"
Debug.Print Error(53)

Error Statement

The Error statement allows you to simulate an error. It is included in VBA for backward compatibility. You should use Err.Raise instead.

In the following code we simulate a “Divide by zero” error.

' https://excelmacromastery.com/
Sub SimDivError()

    On Error Goto eh
        
    ' This will create a division by zero error
    Error 11
    
    Exit Sub
eh:
    Debug.Print Err.Number, Err.Description
End Sub

This statement is included in VBA for backward compatibility. You should use Err.Raise instead.

A Simple Error Handling Strategy

With all the different options you may be confused about how to use error handling in VBA. In this section, I’m going to show you how to implement a simple error handling strategy that you can use in all your applications.

The Basic Implementation

This is a simple overview of our strategy

  1. Place the On Error GoTo Label line at the start of our topmost sub.
  2. Place the error handling Label at the end of our topmost sub.
  3. If an expected error occurs then handle it and continue.
  4. If the application cannot continue then use Err.Raise to jump to the error handling label.
  5. If an unexpected error occurs the code will automatically jump to the error handling label.

The following image shows an overview of how this looks

error-handling

The following code shows a simple implementation of this strategy:

' https://excelmacromastery.com/
Public Const ERROR_NO_ACCOUNTS As Long = vbObjectError + 514

Sub BuildReport()

    On Error Goto eh
    
    ' If error in ReadAccounts then jump to error
    ReadAccounts
    
    ' Do something with the code
    
Done:
    Exit Sub
eh:
    ' All errors will jump to here
    MsgBox Err.Source & ": The following error occured  " & Err.Description
End Sub

Sub ReadAccounts()
    
    ' EXPECTED ERROR - Can be handled by the code
    ' Application can handle A1 being zero
    If Sheet1.Range("A1") = 0 Then
        Sheet1.Range("A1") = 1
    End If
    
    ' EXPECTED  ERROR - cannot be handled by the code
    ' Application cannot continue if no accounts workbook
    If Dir("C:DocsAccount.xlsx") = "" Then
        Err.Raise ERROR_NO_ACCOUNTS, "UsingErr" _
                , "There are no accounts present for this month."
    End If

    ' UNEXPECTED ERROR - cannot be handled by the code
    ' If cell B3 contains text we will get a type mismatch error
    Dim total As Long
    total = Sheet1.Range("B3")
    
    
    ' continue on and read accounts
    
End Sub

This is a nice way of implementing error handling because

  • We don’t need to add error handling code to every sub.
  • If an error occurs then VBA exits the application gracefully.

A Complete Error Handling Strategy

The above strategy has one major drawback. It doesn’t provide any information about the error. It is better than having no strategy as it prevents the application crashing. But that is the only real benefit.

VBA doesn’t fill Err.Source with anything useful so we have to do this ourselves.

In this section, I am going to introduce a more complete error strategy. I have written two subs that perform all the heavy lifting so all you have to do is add them to your project.

The purpose of this strategy is to provide you with the Stack* and line number when an error exists.

*The Stack is the list of sub/functions that were currently in use when the error occurred.

This is our strategy

  1. Place error handling in all the subs.
  2. When an error occurs, the error handler adds details to the error and raises it again.
  3. When the error reaches the topmost sub it is displayed.

We are simply “bubbling” the error to the top. The following diagram shows a simple visual of what happens when an error occurs in Sub3

Error Handling - bubbling

The only messy part to this is formatting the strings correctly. I have written two subs that handle this, so it is taken care of for you.

There are the two helper subs, RaiseError and DisplayError. You can download the library below:

An Example of using this strategy

Here is a simple coding example that uses these subs. In this strategy, we don’t place any code in the topmost sub. We only call subs from it.

' https://excelmacromastery.com/
Sub Topmost()

    On Error Goto EH
    
    Level1

Done:
    Exit Sub
EH:
    DisplayError Err.source, Err.Description, "Module1.Topmost", Erl
End Sub

Sub Level1()

    On Error Goto EH
    
    Level2

Done:
    Exit Sub
EH:
   RaiseError Err.Number, Err.source, "Module1.Level1", Err.Description, Erl
End Sub

Sub Level2()

    On Error Goto EH
    
    ' Error here
    Dim a As Long
    a = "7 / 0"

Done:
    Exit Sub
EH:
    RaiseError Err.Number, Err.source, "Module1.Level2", Err.Description, Erl
End Sub

The result looks like this:

error handling output

If your project has line numbers the result will include the line number of the error:

error handling output line

Error Handling in a Nutshell

  • Error Handling is used to handle errors that occur when your application is running.
  • You write specific code to handle expected errors. You use the VBA error handling statement On Error GoTo [label] to send VBA to a label when an unexpected error occurs.
  • You can get details of the error from Err.Description.
  • You can create your own error using Err.Raise.
  • Using one On Error statement in the top most sub will catch all errors in subs that are called from here.
  • If you want to record the name of the Sub with the error, you can update the error and rethrow it.
  • You can use a log to record information about the application as it is running.

What’s Next?

Free VBA Tutorial If you are new to VBA or you want to sharpen your existing VBA skills then why not try out the The Ultimate VBA Tutorial.

Related Training: Get full access to the Excel VBA training webinars and all the tutorials.

(NOTE: Planning to build or manage a VBA Application? Learn how to build 10 Excel VBA applications from scratch.)

 

Здравствуйте.
Ранее в одной из тем обсуждал причину появления ложных книг в объектной структуре файла.
Выяснилось, что это должно быть связано с ошибкой «Automation error.Разрушительноый сбой» возникающей при его запуске.
Но причину возникновения самой этой ошибки рекомендовали рассмотреть в отдельной теме.
Поэтому прошу помощи в разборе данной проблемы. В чем её причина?
Суть проблемы такова: книга (см. вложенный файл) была создана в Excel 2016, но пару раз запускалась через Excel 2010 (не лиц.).
При запуске возникало сообщение «Automation error. Разрушительный сбой», открывался файл и редактор VBA.
Если ни чего не сохранять и не менять то и пользоваться файлом было нельзя.
Чтобы можно было пользоваться, выделял весь код в том модуле, который открылся автоматически при запуске, комментировал его и сохранял.
После этого сохранял сам файл. При этом команда СОХРАНИТЬ работала, как СОХРАНИТЬ КАК. Файл соответственно сохранял с заменой существующего.
После этого можно было снова пользоваться полученным файлом на Excel 2010 (не лиц.)
После использования этого файла на Excel 2016 история повторялась.

 

Karataev

Пользователь

Сообщений: 2306
Регистрация: 23.10.2014

Наверное Вам надо создать пустой файл, скопируйте в него все листы из имеющегося файла, и скопируйте модули с макросами. С тем файлом, который Вы выложили на форуме, работать наверное нельзя, т.к. если зайти в VBE, то видно, что несколько модулей книг. Такого по идее не должно быть.
Почему такое произошло, я не знаю. Один и тот же файл можно открывать и в Excel 2016 и 2010 — проблем не должно быть.

 

Вот и хотелось причину выяснить.
А то получится, что вместе с листами и модулями и проблема в новый файл перейдет…
Может имена объектов в объектной модели Excel 2016 и 2010 отличаются или имеет значение наличие лиц. ?

 

Karataev

Пользователь

Сообщений: 2306
Регистрация: 23.10.2014

Причину можно искать, но файлом в том виде, какой сейчас есть, мне кажется нельзя пользоваться.
Вроде нет ограничения на использование одного и того же файла в разных версиях, в Майкрософт это предусмотрели и не должно быть сбоев. Если будут какие-то новые объекты, то они не должны приводить к сбою в старых версиях.

 

sokol92

Пользователь

Сообщений: 4446
Регистрация: 10.09.2017

Уважаемый DmitriyBastr! Профессор (

ZVI

) уже наметил для Вашего файла (и аналогичных)

курс лечения

.  :) От себя хочу добавить: перед копированием листов преобразуйте «умные» таблицы в обычные диапазоны.
Версии Excel (2007-2016) для данного случая значения не имеют. О причинах «порчи» можно только гадать…

 

DmitriyBastr

Пользователь

Сообщений: 82
Регистрация: 04.10.2017

#6

21.02.2018 15:00:35

Этим файлом и не пользуются уже.
Но по его образцу будут создаваться другие, более сложные и ответственные. И проблема может повториться.
Поэтому хотелось бы найти причину. Есть подозрение, что она именно в коде, потому что при запуске файла запускается VBE.

Home / VBA / VBA Automation Error (Error 440)

In VBA, Automation Error (440) occurs when you try to access the automation objects (objects that are used by other applications or programming tools). It’s a run-time error that can occur while running a code. As Microsoft says, there could be the following reasons that can make this error occurs:

  1. When you let an application access an object from Excel or create an object that can be used with Excel while using a method or a property with that object this error can occur.
  2. Or you are trying to use an error that has been blocked or disabled by the system administrator.

How to Deal with Automation Error

The best way to deal with the automation error is to use the “On Error Resume Next” statement that moves to the next line of the code irrespective of the error. You can also use the Err object to get information about the source and nature of the error.

Понравилась статья? Поделить с друзьями:
  • Что такое empty cell в excel
  • Что такое editor for excel
  • Что такое analysis for microsoft excel
  • Что такое alt код в word
  • Что такое activex для excel