Windows NT Causes APC Smart UPS Battery to Discharge (170817)


The information in this article applies to:

  • Microsoft Windows NT Server 4.0 Terminal Server Edition
  • Microsoft Windows NT Workstation 4.0
  • Microsoft Windows NT Server 4.0
This article was previously published under Q170817

SYMPTOMS

If, when Windows NT starts, an American Power Conversions (APC) Smart UPS is installed, its battery may be discharged or the UPS function may be shut down if the UPS has been placed in Smart Signaling Mode.

CAUSE

During the boot sequence, Windows NT sends configuration and detection code to the COM port to determine baud rate and FIFO information, and for mouse detection. The string sent to the port may contain the letter D, which the Smart UPS interprets as a command for Calibration Mode.

The Smart UPS interprets the string incorrectly only if it has already been placed in Smart Mode prior to starting Windows NT. The user must have already placed the UPS in Smart Mode using the software supplied by American Power Conversions; otherwise, the Smart UPS will be unaffected by the signal Windows NT sends to the COM ports.

WORKAROUND

To work around this problem, perform either of the following:
  • The adding of the /noserialmice:COMx switch, where x equals the comport number, stops the detection process of a mouse on that port. Also, the latest version of the APC PowerChute Software adds the switch automatically to the Boot.ini file.

    During the installation of a new copy of Windows NT or an upgrade using a compact disc on a local CD-ROM drive and the three boot disks, the only option, when using current retail media, is to disconnect the cable from the system. After Windows NT is installed, reconnect the cable and add the NOSERIALMICE:COMx switch to both lines of the Boot.ini. 
          multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT"
      /NOSERIALMICE:COM1

      multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT
      [VGA mode]" /basevideo /sos /NOSERIALMICE:COM1


    -or-

  • To install the fixed version of Ntdetect.com on a currently installed version, remove the attributes from Ntdetect.com on the root system partition. Copy the new version of Ntdetect.com over and reset the attributes. The default attributes of Ntdetect.com are read-only, archive, and hidden.

RESOLUTION

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

152734 How to Obtain the Latest Windows NT 4.0 Service Pack



If installations or upgrades are done across the network for a version of Windows NT shared on a hard drive, copy the replacement Ntdetect.com over the original.

STATUS

Microsoft has confirmed that this is a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.
Modification Type:MinorLast Reviewed:7/16/2004
Keywords:kb3rdparty kbbug kbfix kbsetup KB170817
©2004 Microsoft Corporation. All rights reserved.