Long-running MAPI 'TaskQ' operation

[This topic is intended to address a specific issue called out by the Exchange Server Analyzer Tool. You should apply it only to systems that have had the Exchange Server Analyzer Tool run against them and are experiencing that specific issue. The Exchange Server Analyzer Tool, available as a free download, remotely collects configuration data from each server in the topology and automatically analyzes the data. The resulting report details important configuration issues, potential problems, and nondefault product settings. By following these recommendations, you can achieve better performance, scalability, reliability, and uptime. For more information about the tool or to download the latest versions, see "Microsoft Exchange Analyzers" at http://go.microsoft.com/fwlink/?linkid=34707.]  

Topic Last Modified: 2007-02-20

Microsoft Exchange Analyzer Tool uses the Exchange Server User Monitor (ExMon) tool to determine whether user MAPI operations are taking longer than should reasonably be expected on a healthy Exchange server.

As part of its analysis, the Exchange Analyzer reviews the ExMon data for user-issued MAPI TaskQ operations that have taken longer than 30 seconds to complete.

TaskQ operations are asynchronous tasks run outside the context of an RPC call. TaskQ and TaskQ User Unknown operations are tasks run at the request of Exchange and include store maintenance. TaskQ User Known operations are asynchronous tasks initiated by a direct user request and include search folder population, sorting, and bulk operations such as move, copy, delete, and marking messages as read on multiple messages.

If the Exchange Analyzer determines that user-issued MAPI TaskQ operations have taken longer than 30 seconds to complete, the Exchange Analyzer displays a warning.

This may not always indicate a performance problem as TaskQ operations are typically operations that can take a long time to finish.

To address this issue, do the following:

  • Consider using the ExMon tool to capture a larger data sample for the Exchange Server Analyzer to review. Because of the large volume of data generated by Exchange, we recommended that the data collection sample be kept to 30 minutes or less.

For More Information

For more information, see the following Exchange Server resources: