Topic Last Modified: 2008-04-22

Microsoft Office Outlook 2003 and later versions include added client-side monitoring features. Client-side monitoring is used to find client errors and latency problems. You can enable client-side monitoring on a server that is running Exchange by modifying the server's registry. When you enable the ClientMonitoringReportLevel registry key with a value of one or two, Outlook 2003 and later versions send data to the server. The data that is sent to the server indicates the status and state of the network connection and includes information about failed RPC requests and error conditions. The server aggregates the information and exposes the information in event log entries. This client monitoring information is collected by the server which can then report the client reported latencies through Performance Monitor (Perfmon.msc).

By default, Exchange Setup does not create the ClientMonitoringReportLevel registry key. The default behavior in Microsoft Exchange Server 2007 is to collect performance data only from all Outlook clients that have high-speed network connectivity. This default behavior is functionally the same as when the value of the ClientMonitoringReportLevel registry key is set to one. Setting the value of the ClientMonitoringReportLevel registry key to two results in collection of performance data from all Outlook 2003 and later versions, regardless of the speed of their network connection speed.

It is important to evaluate the performance of configuring a value of 2 for the ClientMonitoringReportLevel registry key. Because the RPC reporting data has added 14 bytes to the size of the data packet, the performance effect on slow network connections may be significant. Because the server name and information is also specified, this adds an additional 37 bytes of network traffic.

To enable logging client monitoring data to the event log, you must set Client Monitoring under the MSExchangeIS object to Minimum.

When logging has been enabled, the following events are generated:

Outlook 2003 and later versions also have some performance counters which can be useful when troubleshooting client performance issues. For a listing of these counters, see Performance Counter Objects That Are Included in Outlook 2003.

Before You Begin

To perform the following procedure, the account you use must be delegated the Exchange Server Administrators role. For more information about permissions, delegating roles, and the rights that are required to administer Microsoft Exchange Server 2007, see Permission Considerations.

Before you perform the procedure in this topic, be aware that the procedure contains information about how to edit the registry.

Incorrectly editing the registry can cause serious problems that may require you to reinstall your operating system. Problems resulting from editing the registry incorrectly may not be able to be resolved. Before editing the registry, back up any valuable data.
Enabling client-side monitoring can cause server-side performance degradation as a result of the additional data being collected from the Outlook clients by the server that is running Exchange. We recommend that you enable client-side monitoring only when troubleshooting client performance problems.


To modify client-side monitoring levels for Outlook 2003 and later clients

  1. On the server that is running Exchange that contains the client mailboxes to be monitored, start Registry Editor, such as Regedit.exe or Regedt32.exe.

  2. Navigate to: HKLM\System\CurrentControlSet\Services\MSExchangeIS\ParametersSystem

  3. Right-click ParametersSystem and click New | DWORD Value.

  4. Name the new DWORD value ClientMonitoringReportLevel.

  5. Double-click ClientMonitoringReportLevel.

  6. In the Value data field, enter the appropriate value:

    1. 0 = do not collect data from any Outlook 2003 and later clients

    2. 1 = collect performance data only from high-bandwidth Outlook 2003 and later clients (Default Value)

    3. 2 = collect performance data from all Outlook 2003 and later clients

  7. Close the registry editor. The Microsoft Exchange Information Store service automatically detects the changes in minutes, and you do not have to restart the computer or any services.

For More Information

For more information about changing logging levels for Exchange processes, see How to Change Logging Levels for Exchange Processes.