XADM: "Reps-From" USN Too High for One Server

The information in this article applies to:

• Microsoft Exchange Server, versions 4.0 and 5.0

SYMPTOMS

Microsoft Exchange Server administrators may find that newly created objects (for example, recipients) on one server have not replicated to other servers (within a site or between sites), even though a reasonable period of time has passed for replication to have occurred.

The total recipients count (in the lower left corner of the Microsoft Exchange Server Administrator program window) may remain consistently less than that of other servers in the site. Also, users may find that an address is not available in the Global Address List.

CAUSE

The "Reps-From" update sequence number (USN) count on the server not taking replicas from the replicating server has been incorrectly advanced to a value higher than the current USN issued by the target server's directory service.

WORKAROUND

1. The first step in troubleshooting these symptoms is to positively diagnose whether the server's tardy replication is caused by either the problem described in this article or the one in the article Q152942, "XADM: Slow Intra-site Directory Replication Between Servers." These conditions are rare.

2. If you are sure that a server maintains a higher "Reps- From" USN than the highest USN assigned by the that server, do one of the following:

   a. If the high "Reps-From" count is between two replication bridgehead

         servers in a multi-site Microsoft Exchange Server organization:
   

            Redefine one of the other servers in the site lacking replicas as
            the replication bridgehead for the site.
   
          If the server is a single-server site:
   
            Delete the replication connector and the other site object(s)
            associated with this replication connector (in both sites). Allow
            the delete to complete, and then reconfigure the directory
            replication connector.
   
      b. If the high "Reps-From" count is between two servers within a site,
         Re-install the server harboring the high "Reps-From" count into the
         site, following the steps documented in Microsoft Knowledge Base
         article Q162353, "XADM: Restoring an Exchange Directory."
   
   

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server versions 4.0 and 5.0. A supported fix to this problem in Microsoft Exchange version 4.0 is in development, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information on the availability of this fix.

This problem was corrected in the latest Microsoft Exchange 5.0 Server U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K

MORE INFORMATION

For additional information, please see the following articles in the Microsoft Knowledge Base:

   ARTICLE-ID: Q152942
   TITLE     :XADM: Slow Intra-site Directory Replication Between Servers

   ARTICLE-ID: Q162353
   TITLE     : XADM: Restoring an Exchange Directory

Keywords          : kbbug4.00 kbbug5.00 kbfix5.00.sp1 XADM kbusage
Version           : winnt:4.0,5.0
Platform          : WINDOWS