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Stop 0xC000021A When Starting Task Manager with CTRL+ALT+DEL
Article ID: 183840 - View products that this article applies to.
This article was previously published under Q183840
The Task Manager can be started by pressing CTRL+ALT+DEL and then clicking Task Manager on the Security dialog box. However, if there are many user environment variables defined, running Task Manager from the Security dialog box may cause a STOP C000021A exception error message.
The System Environment Block becomes corrupted by the Winlogon service if the size of the User Environment is significantly large. This can also be caused by the installation of many applications on a system.
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:
(http://support.microsoft.com/kb/152734/EN-US/ )How to Obtain the Latest Windows NT 4.0 Service Pack
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.
Article ID: 183840 - Last Review: November 1, 2006 - Revision: 2.2