FIX: ActiveX Document DLL Causes GPF When Unloading Modal Form

• Microsoft Visual Basic Control Creation, Learning, Professional, and Enterprise Editions for Windows, version 5.0

SYMPTOMS

A General Protection Fault (GPF) occurs in Internet Explorer when using ActiveX UserDocument DLL.

CAUSE

This behavior occurs when you attempt to unload a form within the Paint Event.

RESOLUTION

This problem has been fixed in SP2. Visual Basic now catches the error and posts an error message stating that the form can not be unloaded in this context.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This bug has been fixed in Visual Studio 97 Service Pack 2.

For more information on the Visual Studio 97 Service Pack 2, please see the following article in the Microsoft Knowledge Base:

Q170365 : INFO: Visual Studio 97 Service Packs - What, Where, and Why

Q171554 : INFO: Visual Basic 5.0 Fixes in Visual Studio 97 Service Pack 2

MORE INFORMATION

Steps to Reproduce Behavior

1. Start a new ActiveX Document DLL project. UserDocument1 is created by default.



2. Add a CommandButton (Command1) to UserDocument1.



3. Add the following code to the Click event of Command1:

   
         Private Sub Command1_Click()
            Dim x As New Form1
            x.Show vbModal
         End Sub
    




4. Add a Form (Form1) to the project.



5. Add the following code to the Paint event of Form1:

   
         Private Sub Form_Paint()
            Unload Me
         End Sub
    




6. Press the F5 key to run the project.



7. Load the UserDocument1.vbd from the Visual Basic installation directory into Internet Explorer.



8. Click on Command1 button.

Additional query words: kbDSupport

Keywords : kbVBp500 kbVS97sp2fix kbGrpVB kbvbp500sp2fix
Version : 5.0
Platform : WINDOWS
Issue type : kbbug