Q241589: Kernel Access Fault in Windows Terminal Server

Article: Q241589
Product(s): Microsoft Windows NT
Version(s): winnt:4.0 SP4
Operating System(s): 
Keyword(s): kbtool
Last Modified: 11-DEC-2001

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The information in this article applies to:

- Microsoft Windows NT Server version 4.0 SP4, Terminal Server Edition 
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SYMPTOMS
========

Sessions to Terminal Server users may disappear on retail builds of Windows NT
4.0, Terminal Server Edition (sessions that are not connected to a Windows NT
debugger session).

CAUSE
=====

The way certain programs paint the screen can cause the Remote Desktop Protocol
(RDP) to use an uninitialized variable and bugcheck the server.

This problem aggravates a path in SDGSendSDARect, which has an uninitialized
variable for one rare path (bitmaps with a height of 1 and a width greater than
or equal to 12). This uninitialized variable can affect later invocations of the
function by causing a problem with a compression estimate that uses certain
assumptions. When this problem occurs (a kernel access fault,) an error message
appears. It is seen in the form of a disappearing session to a user on retail
builds of Windows NT 4.0, Terminal Server Edition (that are not connected to a
Windows NT debugger session).


RESOLUTION
==========

To resolve this problem, obtain the latest service pack for Windows NT Server
4.0, Terminal Server Edition. For additional information, please see the
following article in the Microsoft Knowledge Base:

  Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products that are
listed at the beginning of this article.


Additional query words:

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Keywords          : kbtool 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbNTTermServ400sp4 kbNTTermServSearch
Version           : winnt:4.0 SP4
Issue type        : kbbug
Solution Type     : kbfix

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