Q161768: SNALINK.EXE - Cancel Timeout in \driver\DLC

Article: Q161768
Product(s): Microsoft SNA Server
Version(s): WINDOWS:2.0,2.1,2.11,2.11 SP1,3.0,4.0; winnt:3.5,3.51,4.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-JUN-2002

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The information in this article applies to:

- Microsoft SNA Server, versions 2.0, 2.1, 2.11, 2.11 SP1, 3.0, 4.0 
- Microsoft Windows NT Server versions 3.5, 3.51, 4.0 
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IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

  Q256986 Description of the Microsoft Windows Registry

SYMPTOMS
========

When you stop the SNA Server service, the following error message may be
displayed:

  SNALINK.EXE - Cancel Timeout
  The driver \driver\DLC failed to complete a cancelled I/O request in the
  allotted time.

After clicking OK, the same message may appear over and over again. You may not
be able to perform any other operations until this error is cleared.


CAUSE
=====

The error message is a Windows NT "hard error popup" which occurs if the SNA
Server 802.2 link service terminates while the underlying DLC.SYS driver has
completed IRP's to return to the calling thread. However, the link service has
already ended. This error causes Windows NT to report a system-modal hard error
popup which freezes the application subsystem until the user cancels the dialog.
If multiple IRP's are completing, each IRP will cause another popup to appear.

This problem will only occur when the SNA Server service is stopped, which causes
underlying SNA Server link services to stop too.

RESOLUTION
==========

WARNING: If you use Registry Editor incorrectly, you may cause serious problems
that may require you to reinstall your operating system. Microsoft cannot
guarantee that you can solve problems that result from using Registry Editor
incorrectly. Use Registry Editor at your own risk.

While this error may occur during SNA Server shutdown, it is recommended that the
hard error popup be suppressed by configuring the following Windows NT registry
setting:

  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Windows\ ErrorMode:
  REG_DWORD: 2

The default is 0 which causes the error popup to appear, requiring the user to
manually clear the error. This option is not recommended for Windows NT servers
which may not be accessible to users. A value of 2 causes the error to be
reported to the event log and returns OK to the hard error so the system can
continue. Popups don't appear. This entry is described in the Windows NT 3.5
Resource Kit Volume 4 "Optimizing Windows NT", Appendix B on page 614.

STATUS
======

Microsoft has confirmed this to be an operational issue with Windows NT version
3.5, 3.51, and 4.0. It is recommended that the ErrorMode entry is modified for
servers which aren't normally accessible to administrator personnel.

Additional query words:

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT351search kbWinNT350search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ200 kbSNAServ211 kbSNAServ400 kbSNAServ210 kbSNAServ211SP1
Version           : WINDOWS:2.0,2.1,2.11,2.11 SP1,3.0,4.0; winnt:3.5,3.51,4.0
Issue type        : kbprb

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