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Q171493: FIX: Viewing Property Pages and Exiting Causes Memory Leak

Article: Q171493
Product(s): Microsoft Visual Basic for Windows
Version(s): 5.0
Operating System(s): 
Keyword(s): kbVBp500 kbVS97sp2fix kbGrpDSVB kbvbp500sp2fix
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Control Creation Edition for Windows, version 5.0 
- Microsoft Visual Basic Learning Edition for Windows, version 5.0 
- 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
========

Viewing property pages several times and exiting causes a memory leak.

CAUSE
=====

The Visual Basic IDE fails to release its object property list before
re-allocating space for a new list.

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

For a list of the Visual Basic 5.0 bugs that were fixed in the Visual Studio 97
Service Pack 2, please see the following article in the Microsoft Knowledge
Base:

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

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

The detection of this problem requires a memory checker or debug version of
Visual Basic.

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

1. Start a new Standard EXE project. Form1 is created by default.

2. On Form1, place a Toolbar control (from Comctl32.ocx - Windows Common
  Controls 5.0).

3. Right-click the Toolbar control to bring up the context menu.

4. Select Properties from the context menu.

5. Click either the "OK" or the "Cancel" button of the property page.

6. Repeat steps 3-5.

7. Click File, Exit. Say "No" to the question "Save changes to the following
  files?"

Upon exiting, the Debug version of Visual Basic will raise the error:

  "Heap Memory leak detected."

Results by third-party memory checkers may vary.

Additional query words:

======================================================================
Keywords          : kbVBp500 kbVS97sp2fix kbGrpDSVB kbvbp500sp2fix 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVBA500Search kbVBA500 kbVB500 kbZNotKeyword3
Version           : 5.0
Issue type        : kbbug
Solution Type     : kbfix

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