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Q139058: Battery Shutdown Signal Delayed Using Windows NT UPS Service

Article: Q139058
Product(s): Microsoft Windows NT
Version(s): winnt:3.51
Operating System(s): 
Keyword(s): kbenv kbhw kbui kbHardware
Last Modified: 08-AUG-2001

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The information in this article applies to:

- Microsoft Windows NT Workstation version 3.51 
- Microsoft Windows NT Server version 3.51 
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SYMPTOMS
========

If your computer runs Windows NT with an uninterruptable power supply (UPS) and
the Windows NT UPS service installed and a power failure occurs, the UPS service
initiates the Windows NT shutdown. One of the following symptoms occur when the
battery shutdown signal is sent to the battery and the battery shuts down and
turns off the computer:

- Windows NT shuts down and then restarts or has already rebooted again before
  the UPS turns off the computer.

  -or-

- Windows NT shuts down just in time when the computer turns off.

  NOTE: This is not a problem.

  -or-

- Windows NT is still in the process of shutting down when the computer turns
  off.

CAUSE
=====

The length of time the UPS waits before turning off the computer, also called
the Shutdown Wait, is hard coded to two minutes.

The UPS service has no way of knowing exactly when the shut down of Windows NT is
complete, because the UPS service runs in User Mode.

WORKAROUND
==========

To customize the Shutdown Wait period to your computer, install the fix
mentioned below and change your registry as follows:

WARNING: Using Registry Editor incorrectly can cause serious, system-wide
problems that may require you to reinstall Windows NT to correct them. Microsoft
cannot guarantee that any problems resulting from the use of Registry Editor can
be solved. Use this tool at your own risk.

1. Ensure that you have the following three options enabled in Control Panel UPS
  and that the UPS device has the capability to perform these options:

  - Power Fail Signal
  - Low Battery Signal
  - Remote UPS Shutdown

2. Run Registry Editor (REGEDT32.EXE).

3. From the HKEY_LOCAL_MACHINE subtree, go to the following key:

  \SYSTEM\CurrentControlSet\Services\UPS

4. From the Edit menu, choose Add Value.

5. Add the following:

  Value Name: ShutdownWait
  Data Type: REG_DWORD
  Data: <0 to 600 seconds>

  NOTE: The default wait time is still two minutes.

6. Choose OK and quit Registry Editor.

7. Shut down and restart Windows NT.

RESOLUTION
==========

This problem has been corrected in the latest Service Pack for Windows NT
version 3.51.

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT version 3.51. This
problem was corrected in the latest Windows NT 3.51 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: prodnt

======================================================================
Keywords          : kbenv kbhw kbui kbHardware 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNT351search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS351 kbWinNTS351search
Version           : winnt:3.51

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

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