Winlogon.exe Access Violation When KillScreenSaver Function Calls CloseObjectMonitorObject with "ScreenSaverData->Monitor = NULL" (329484)



The information in this article applies to:

  • Microsoft Windows NT Server 4.0
  • Microsoft Windows NT Server 4.0 SP6
  • Microsoft Windows NT Server 4.0 SP6a
  • Microsoft Windows NT Workstation 4.0
  • Microsoft Windows NT Workstation 4.0 SP6
  • Microsoft Windows NT Workstation 4.0 SP6a
  • Microsoft Windows NT Server, Enterprise Edition 4.0
  • Microsoft Windows NT Server, Enterprise Edition 4.0 SP6
  • Microsoft Windows NT Server, Enterprise Edition 4.0 SP6a

This article was previously published under Q329484

SYMPTOMS

On a Windows NT 4.0-based system, you may receive a "0xC000021A" error message on a blue screen when you enable a screen saver.

CAUSE

This issue occurs when you use the KillScreenSaver function to call the CloseObjectMonitorObject function with the following code:
ScreenSaverData->Monitor = NULL
This generates an exception in Winlogon.

RESOLUTION

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   09-Oct-2002  00:17  4.0.1381.7197     193,296  Winlogon.exe     			
Note Because of file dependencies, you must be running Windows NT 4.0 Service Pack 6a before you install this hotfix.

STATUS

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

Modification Type:MinorLast Reviewed:9/27/2005
Keywords:kbHotfixServer kbQFE kbQFE kbbug kbfix KB329484