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Q177703: FIX: Access Violation with Public Enums in UserControl

Article: Q177703
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0
Operating System(s): 
Keyword(s): kbCtrlCreate kbVBp kbVBp500bug kbVBp600fix kbVS97sp2 kbGrpDSVB kbDSupport kbControl
Last Modified: 27-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, version 5.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 5.0 
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SYMPTOMS
========

When exiting a Visual Basic 5.0 ActiveX Control project in the design
environment, an Access Violation error occurs and Visual Basic is terminated.

CAUSE
=====

This problem can occur when declaring Public Enum in the UserControl module when
running Visual Studio 97 Service Pack 2 (SP2.)


RESOLUTION
==========

Move the Public Enums to a standard (.bas) module instead of the UserControl
module.

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 Basic 6.0.

MORE INFORMATION
================

Steps to Reproduce Behavior
---------------------------

NOTE: To reproduce the problem, you must have Visual Studio 97 Service Pack 2
installed.

1. Create a new ActiveX control project.

2. Add another UserControl to the project so you have UserControl1 and
  UserControl2.

3. Place UserControl2 inside UserControl1.

4. Add the following code to UserControl1:

        Option Explicit

        Public Enum BorderStyle_Type
           None = 1
           FixedSingle = 2
        End Enum

        Public Enum Appearance_Type
           Flat = 1
           ThreeDimensional = 2
        End Enum

5. Close the design windows of UserControl1 and UserControl2.

6. Add a Standard EXE project so that you have a project group. Form1 is created
  by default.

7. Add UserControl1 to Form1.

8. Optional: Save the project group.

9. Exit Visual Basic to close the project group.

  In Windows 2000, you receive the following error:

  The instruction at "0x0fb20cc8" referenced memory at "0x00000010". The memory
  could not be read.

  In Windows NT 4.0, Service Pack 3 you receive the following error:

  Access Violation in VB5.exe at 0x0fb25f69

  In Windows 95, Windows 98, or Windows Me, you receive the following error:

  VB5 caused an invalid page fault in module VBA5.DLL

Additional query words: IPF GPF crash

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Keywords          : kbCtrlCreate kbVBp kbVBp500bug kbVBp600fix kbVS97sp2 kbGrpDSVB kbDSupport kbControl 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVBA500 kbVB500
Version           : :5.0
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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