Tapisrv.exe Thread Uses Excessive CPU Time

ID: Q154387

The information in this article applies to:

Microsoft Windows NT Workstation version 4.0
Microsoft Windows NT Server version 4.0
Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

A thread in Tapisrv.exe begins using an excessive amount of processor time (as much as 95% to 100%) when you run a TAPI server application under a heavy load of phone calls.

CAUSE

This problem occurs when the thread that is using all the processor time has become stuck in an infinite loop due to a problem in the ring management code.

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, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

NOTE: This hotfix requires TAPI 2.1. Applying this hotfix with a previous version of TAPI may cause unpredictable behavior.

STATUS

Microsoft has confirmed this to be 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.

Additional query words: 4.00

Keywords : kbenv kbtool NT4SP4Fix kbbug4.00 kbfix4.00.sp4 NTSrvWkst ntutil
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug