The Availability Service was unable to log on as the network service context for proxying requests

 

Topic Last Modified: 2008-05-07

The Microsoft Exchange Server 2007 Management Pack for Operations Manager monitors the Windows Application log on computers that are running Exchange Server 2007 and generates this alert when the event or events specified in the following Details table are logged.

To learn more about this event, do one or more of the following:

  • Review the description of the event that includes the variables specific to your environment. From the Operator Console, select this alert, and then click the Properties tab.

  • Review all events that have been logged that meet the criteria of this Operations Manager alert. From the Operator Console, click the Events tab, and then double-click the event in the list for which you want to review the event description.

Details

Product Name

Exchange

Product Version

8.0 (Exchange Server 2007)

Event ID

4016

Event Source

MSExchange Availability

Alert Type

Warning

MOM Rule Path

Microsoft Exchange Server/Exchange 2007/Client Access/Information Worker

MOM Rule Name

Availability Service was unable to log on as network service context for proxying requests.

Explanation

This Error event indicates that the Microsoft® Exchange Availability service did not logon as a network service. The Exchange Availability service retrieves the Schedule+ Free Busy and Out-Of-Office (OOF) data for a set of mailboxes residing on a computer that is running Exchange Server 2007. When the Exchange Availability service cannot directly connect to a mailbox that resides in a remote Active Directory directory service forest, it sends a proxy Web request to another instance of the Exchange Availability service that is running in the remote Active Directory forest by using Kerberos authentication. If Kerberos authentication fails, Network LAN Manager (NTLM) authentication is used. Under NTLM authentication, the Web request for a cross-site or cross-forest Exchange Availability service that is running under the context of a local computer uses an Anonymous user account.

The cross-site or cross-forest Availability service cannot authenticate an incoming Web request that uses an Anonymous user account. Therefore, the cross-site or cross-forest Availability service must impersonate the network service context. This means that even under NTLM authentication, the Web request for cross-site or cross-forest Exchange Availability service uses a local computer account. This event is logged when the Exchange Availability service does not create the network service authentication context.

User Action

To resolve this error, contact Microsoft Product Support Services. For more information, visit the Microsoft Help and Support Web site.

For More Information

To search the Microsoft Knowledge Base articles based on criteria that generated this alert, visit the Search the Support Knowledge Base (KB) Web site.

To review Exchange 2007 event message articles that may not be represented by Exchange 2007 MOM alerts, see the Events and Errors Message Center.

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.