DOCUMENT:Q186273  30-MAY-1998  [vbwin]
TITLE   :BUG: AV Running VB5-Built Component in Multi-Threaded Environmen
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:5.0,97,97sp1,97sp2,97sp3
OPER/SYS:WINDOWS
KEYWORDS:kbVBp500bug

======================================================================
---------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Visual Basic Professional and Enterprise Editions for
   Windows, version 5.0
 - Microsoft Visual Studio versions 97, 97sp1, 97sp2, 97sp3
---------------------------------------------------------------------

SYMPTOMS
========

When running an apartment model DLL created in Visual Basic 5.0 in a
Multi-threaded environment such as Microsoft Internet Information
Server (IIS) or Microsoft Transaction Server (MTS), the DLL fails
periodically with an access violation (AV).

RESOLUTION
==========

The following steps may be used to change the DLL to avoid the problem.
This may not resolve the issue in all cases.

Step-by-Step Example
--------------------

1. Add a class module to the project.

2. Set the name of the class to clsEmpty.

3. Set the Instancing property of the class to 2-PublicNotCreatable.

4. In Project Properties, set the Start Up Object to Sub Main.

5. Add a BAS module, or put the following in an existing BAS module in the
   project:

      Public gEmpty As clsEmpty
      Public Sub main()
         Set gEmpty = New clsEmpty
      End Sub

6. Save the project and re-compile.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products
listed at the beginning of this article. We are researching this
bug and will post new information here in the Microsoft Knowledge
Base as it becomes available.

Additional query words: MTS IIS crash gpf ipf kbVBp500bug kbDSupport kbdss
======================================================================
Keywords          : kbVBp500bug
Version           : WINDOWS:5.0,97,97sp1,97sp2,97sp3
Platform          : WINDOWS
Issue type        : kbbug
Solution Type     : kbpending

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

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