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Q305723: PRB: COM Application Hangs When CoCreateInstance Is Called from

Article: Q305723
Product(s): Microsoft Programming Utilities
Version(s): 
Operating System(s): 
Keyword(s): 
Last Modified: 09-MAY-2002

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The information in this article applies to:

- Microsoft COM 
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SYMPTOMS
========

When you call the CoCreateInstance function from the DllMain function, the
Component Object Model (COM) application hangs.

CAUSE
=====

CoCreateInstance may start a thread that tries to call the DllMain function of
all dynamic-link libraries (DLLs) that exist in the process by passing a
DLL_THREAD_ATTACH value. Because the call originates from DllMain, and because
DllMain is not a reentrant function, the call to CoCreateInstance never returns.

RESOLUTION
==========

To resolve this problem, do not call CoCreateInstance from DllMain. You can move
the call to an initialization function or to any other function that is called
later.

STATUS
======

This behavior is by design.

Additional query words:

======================================================================
Keywords          :  
Technology        : kbAudDeveloper kbCOM kbCOMPlusSearch kbComSearch
Version           : :
Issue type        : kbprb
Solution Type     : kbnofix

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