Public folder store present on front-end server

[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]  

Topic Last Modified: 2006-09-07

The Microsoft® Exchange Server Analyzer Tool queries the Active Directory® directory service to determine whether a public folder store is present on each Exchange server. If the Exchange Server Analyzer finds that the InformationStore object is of object class, msExchPublicMDB, the server is hosting a public folder store.

The Exchange Server Analyzer also queries the MicrosoftExchangeV2 Microsoft Windows® Management Instrumentation (WMI) class to determine whether a value is set for the IsFrontEndServer key. A value of True indicates the Exchange server is configured as a front-end server and a value of False indicates the Exchange server is not configured as a front-end server. If the Exchange Server Analyzer finds that an Exchange server configured as a front-end server is hosting a public information store, a warning is displayed.

It is recommended that you not run public folder stores on front-end servers. Public folder stores are not required on front-end servers, because front-end servers do not host mailboxes. In addition, there are known issues with public folder replication, public folder referrals, and memory leaks when public folder stores are located on front-end servers running Exchange 2000 Server. Therefore, you should dismount all public folder stores on all front-end servers.

After you dismount the public folder stores, you can disable the Microsoft Exchange Information Store service because it no longer performs any functions on the front-end servers. By removing unnecessary services, you reduce loading and improve security and performance.

If the front-end server also receives Simple Mail Transfer Protocol (SMTP) messages from the Internet, the Microsoft Exchange Information Store service should remain running, and a mailbox store must remain mounted. However, you should never have a public folder store on a front-end server.

  1. In Exchange System Manager, expand Servers, expand your server, and then expand First Storage Group.

    Right-click Mailbox Store (ServerName), click Dismount Store, and then click Yes to dismount the store.

    If you use the front-end server as an SMTP-bridgehead server, you must have a mailbox store mounted on the server. In this case, do not dismount and delete this store, but make sure you do not have any mailboxes stored on this server.
  2. Right-click Mailbox Store (ServerName), and then click Properties.

  3. Click the Database tab, select the Do not mount this store at startup check box, and then click OK.

    Right-click Public Folder Store (ServerName), and then click Dismount Store.

    Before you dismount the public folder store, make sure that the public folders have a replica on another public folder store. Otherwise, you may lose information.
  4. Click Yes to dismount the public folder store.

  1. In the Services Microsoft Management Console (MMC) snap-in, right-click Microsoft Exchange Information Store in the Name list, and then click Properties.

  2. In the Startup type list, select Disabled, and then click Stop.

For more information about issues related to running store services on front-end servers, see the following Microsoft Knowledge Base articles:

For more information about front-end and back-end servers, see the Exchange Server 2003 and Exchange 2000 Server Front-End and Back-End Topology guide (