DOCUMENT:Q160650  10-AUG-2001  [winnt]
TITLE   :Blue Screen When Closing Kernel Mode Handles from User Mode
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:4.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Workstation version 4.0 
 - Microsoft Windows NT Server version 4.0 
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SYMPTOMS
========

User mode programs that close a handle that was opened up by a kernel mode
component may cause a blue screen error message.

CAUSE
=====

In Windows NT 3.51, if this happened, the handle became invalid. In Windows NT
4.0, if a kernel mode component closed an already closed handle, a blue screen
error would occur. A user mode application has no way of knowing who closed the
handle. A user mode application should never close a handle opened by that
application in kernel mode.


STATUS
======

Microsoft has confirmed this to be a problem in Microsoft Windows NT version
4.0.
This problem was corrected in the latest Microsoft Windows NT 4.0 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:

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Keywords          :  
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : winnt:4.0

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