Deadlock in TAPI Service If the Provider Is Not Re-entrant

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Article ID: 262290 - View products that this article applies to.
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When a program makes a call to the Telephony application programming interface (TAPI) lineClose function, CPU usage may rise to 100 percent if the provider is not re-entrant.


This behavior is caused by a deadlock condition that may occur in the TAPI service. It occurs only with providers that are not re-entrant.

This behavior may occur if the following items occur in quick succession in the listed order:
  • The provider signals a new call on a particular line, by using LINE_NEWCALL.
  • The program closes the line by making a call to lineClose.
  • The provider sends the first LINE_CALLSTATE message for the new call.
When this occurs, a deadlock may occur in the TAPI service.


To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
260910 How to Obtain the Latest Windows 2000 Service Pack
The English version of this fix should have the following file attributes or later:
   Date        Time    Version        Size      File name
   05/06/2000  04:02p  5.0.2195.2085  173,328  Tapisrv.dll


Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows 2000 Service Pack 2.


Article ID: 262290 - Last Review: October 20, 2013 - Revision: 3.4
  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional Edition
kbnosurvey kbarchive kbhotfixserver kbqfe kbbug kbfix kbwin2000presp2fix KB262290

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