DOCUMENT:Q151202  13-JUN-2001  [sna]
TITLE   :TN3270E May Experience Unexpected Application Exception Errors
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:2.11,2.11 SP1
OPER/SYS:
KEYWORDS:kbnetwork

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The information in this article applies to:

 - Microsoft SNA Server, versions 2.11, 2.11 SP1, on platform(s):
    - the operating system: Microsoft Windows NT 
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SYMPTOMS
========

The SNA Server 2.11 Service Pack 1 Tn3270E Server may experience intermittent
and random access violations.

If this occurs, the SNA Server TN3270E service will log the following event in
the Microsoft Windows NT application event log:

   Event Id:5
   The TN3270E Service has abnormally terminated.

   EXPLANATION
   An exception (0xC0000005) has occurred that has caused the TN3270E
   Service to terminate.

   ACTION
   Record message and contact technical support.

CAUSE
=====

The TN3270E Server user license validation routine was accessing the global
queue of session control blocks without using a critical section to serialize
access to the queue. This leaves a chance that while it is accessing a control
block that control block could be deleted by another thread.


STATUS
======

Microsoft has confirmed this to be a problem in Microsoft SNA Server versions
2.11 and 2.11.sp1. A fix to this problem is in development, but has not been
regression-tested and may be destabilizing in production environments. Microsoft
does not recommend implementing this fix at this time. Contact Microsoft Product
Support Services for more information on the availability of this fix.

Additional query words: prodsna tn3270

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Keywords          : kbnetwork 
Technology        : kbAudDeveloper kbSNAServSearch
Version           : WINDOWS:2.11,2.11 SP1
Issue type        : kbbug

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