Topic Last Modified: 2010-04-28

The Microsoft Exchange Server 2010 Management Pack for System Center Operations Manager monitors the Windows Application log on computers running Exchange 2010 and generates this alert when the events specified in the following Details table are logged.

To learn more about this alert, in Operations Manager, do one or more of the following:


Product Name


Product Version

14.0 (Exchange 2010)

Event ID


Event Source


Alert Type


Rule Path

Microsoft Exchange Server/Exchange 2010/Mailbox/System Attendant

Rule Name

OABGen is configured to generate version 2 or version 3 OAB files for an offline address book, but there is no public folder server available.


This Warning event indicates that offline address book (OAB) versions prior to version 4 cannot be generated because a public folder server containing a replica of the OAB system folder cannot be contacted. Another symptom may be that users of some versions of Outlook and Outlook Web App will be unable to view their address books.

This warning event may occur when both of the following are true:

  • The Enable public folder distribution option is enabled on the properties of the default OAB.

  • At least one public folder database is not online.

This event may also occur if the OAB folder does not properly exist or have a valid replica. This situation may occur in cases where an administrator creates a new OAB, designates the public folder database on server <ServerName> as the site folder server, and then the designated public folder database is subsequently deleted incorrectly. For example:

  • If you fail to remove a replica before deleting a public folder database.

  • If you remove a public folder database object from Active Directory.

  • If you removed Exchange from a computer on which the public folder database was located.

This event may also occur if the OAB folder has been created, but hierarchy replication or maintenance has not occurred. In this scenario, the OAB folder was not created but the OAB object exists in Active Directory. Active Directory lists a deleted public folder database as the designated site folder server and OAB folders do not exist anywhere in the Exchange organization.

User Action

To resolve this error, do one or more of the following:

For More Information

If you are not already doing so, consider running the Exchange tools created to help you analyze and troubleshoot your Exchange environment. These tools can help make sure that your configuration aligns with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. To run these tools, go to the Toolbox node of the Exchange Management Console. To learn more about these tools, see Managing Tools in the Toolbox.