XFOR: Exchange Dir-Sync Failing with Event ID 134

• Microsoft Exchange Server, version 4.0

SYMPTOMS

After you apply Microsoft Exchange Server Service Pack 3, directory synchronization (dir-sync) between Microsoft Exchange Server and Microsoft Mail fails. After you turn up diagnostic logging on the Microsoft Exchange directory synchronization agent (DXA), the following event ID appears in the application event log:

   Event ID: 134
   Type: Error
   Source: MSExchangeDX
   Category: Event Handler
   Description:
   Error MH_RC_SESSION_BUSY returned by the MTA. (Thread 812).

CAUSE

Copying the Microsoft Mail Administrator mailbox on outgoing (from Microsoft Exchange Server) dir-sync messages (whether the computer running Microsoft Exchange Server is a dir-sync server or requestor) and then deleting these messages from both the Inbox and Deleted Items folder without reading them causes a non-read notification (NRN) to be returned to the Message Transfer Agent (MTA). The MTA fails during message conversion (MDBEF -> P2) and the message is incorrectly handled.

WORKAROUND

To prevent this problem, do the following:

• Don't copy the dir-sync administrator on dir-sync messages.
• Don't delete the dir-sync messages.
• Open the messages before deleting them.

RESOLUTION

Apply the fix referenced below. The MTA code was fixed to properly handle the message conversion.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange version 4.0. This problem was corrected in the latest Microsoft Exchange 4.0 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