DOCUMENT:Q138388  12-JUN-2001  [sna]
TITLE   :Dynamically Loading/Unloading WINRUI32.DLL Causes System Hang
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:2.0,2.1,2.11
OPER/SYS:
KEYWORDS:

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

 - Microsoft SNA Server, versions 2.0, 2.1, 2.11 
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SYMPTOMS
========

When you dynamically load and unload the WINRUI32.DLL, your computer hangs. This
symptom occurs sporadically.

CAUSE
=====

This problem occurs during a call to FreeLibrary (hLibModule) where hLibModule
was previously set to the result of a call to LoadLibrary (WINRUI32.DLL).

The hang occurs when the WINRUI32.DLL is unloaded by the FreeLibrary()call. The
hang is caused by WINRUI32.DLL trying to remove its DMOD routing procedure
during DLL detach processing. There are certain procedures that cannot be
reliable performed inside detach processing, for example, waiting for something
like the DMOD routing proc table to become available.

Existing applications that do not call WinRUIStartup/WinRUICleanup continue to
function as before.

RESOLUTION
==========

Microsoft has updated the file LIBS\WIN32WINRUI32.DLL to correct this problem.


The fix to the WINRUI32.DLL removes the RUI routing procedure during the
processing of the WinRUICleanup() call and ensures that the DLL detach
processing does not attempt to do it again. To properly load and unload the DLL
you need to always call WinRUIStartup before your first RUI verb and
WinRUICleanup before freeing the WINRUI32.DLL.

STATUS
======

Microsoft has confirmed this to be a problem in SNA Server for Windows NT. This
problem was corrected in the latest SNA Server for Windows NT, 2.11 U.S. Service
Pack. For information on obtaining the Service Pack, query on the following word
in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K

Additional query words: prodsna 2.00 2.10

======================================================================
Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ200 kbSNAServ211 kbSNAServ210
Version           : WINDOWS:2.0,2.1,2.11
Issue type        : kbbug
Solution Type     : kbfix

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

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