FIX: MTS or IIS with ODBC Connection Pooling May Hang If Database Becomes Unavailable (274569)

The information in this article applies to:

Microsoft Internet Information Server 4.0
Microsoft Transaction Server 2.0
Microsoft Data Access Components 2.1 SP2

This article was previously published under Q274569

SYMPTOMS

When ODBC connection pooling is enabled, if database servers are down or unavailable due to network connectivity issues, Internet Information Server (IIS) or Microsoft Transaction Server (MTS) may stop responding (hang).

CAUSE

This behavior is caused by a bug in the resource dispenser (Mtxdm.dll). The threads that perform connection pooling wait for the ODBC thread that is trying to perform an ODBC call, which results in a deadlock condition.

RESOLUTION

The resource dispenser has been modified to resolve this problem. To obtain the corrected version of Mtxdm.dll, install Microsoft Data Access Components (MDAC) version 2.5 or later from the following Microsoft Web Site:

http://msdn.microsoft.com/dataaccess

You can also obtain this fix by installing Microsoft Windows NT 4.0 Service Pack 6a or later. For more information, see the following Web site:

http://www.microsoft.com/ntserver/

STATUS

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

This problem has been corrected in MDAC version 2.5 and later, and in Windows NT 4.0 Service Pack 6a and later.

Modification Type:	Major	Last Reviewed:	11/18/2003
Keywords:	kbbug kbfix kbQFE KB274569