XCON: NDR from Malformed Message Not Received

• Microsoft Exchange Server, version 5.5

SYMPTOMS

When you send a message to an X.400 recipient, or reply to a message sent from an X.400 recipient, the message might not be successfully delivered and you might not receive a Non-Delivery Report (NDR). This can occur if an organization has a second X.400 connector with an overlapping address space and if the message cannot be converted to X.400 successfully. The Windows NT Event Viewer Application log on the Exchange Server with the X.400 Connector will have events logged such as:

   Event 210: X.400 Service Event, severity 14
   (MTA DISP:FANOUT(12) Proc 112) 01-23-98 10:24:31am
   Content conversion failed
   Object at fault     0600002D
   Conversion error    258
   MTS Identifier      C=US;A= ;P=LAB;L=LAB_RED-980123152503Z-601
   Old content type    2A864886F7140501
   New content type    56010A01
   PDU dump reference  2

   Event 62: X.400 Service Event, severity 12
   (MTA DISP:FANOUT(12) Proc 112) 01-23-98 10:24:31am
   Delivery failure
   X.400 reason code     unable-to-transfer
   X.400 diagnostic code content-syntax-error
   Internal qualifier    0
   MTS Identifier C=US;A= ;P=LAB;L=LAB_RED-980123152503Z-601

   Event 287: X.400 Service Event, severity 12
   (MTA DISP:RESULT(17) Proc 436) 01-23-98 10:24:31am
   Successful rerouting
   MTS Identifier    C=US;A= ;P=LAB;L=LAB_RED-980123152503Z-601
   New Connector     /O=LAB/OU=GREEN2/CN=CONFIGURATION/CN=CONNECTIONS/CN=SITE CONNECTOR (RED)
   New Target entity /O=LAB/OU=RED/CN=CONFIGURATION/CN=SERVERS/CN=LAB_RED/CN=MICROSOFT MTA
   Old Connector     /O=LAB/OU=GREEN2/CN=CONFIGURATION/CN=CONNECTIONS/CN=X400 TO BECTOGO
   Old Target entity /O=LAB/OU=GREEN2/CN=CONFIGURATION/CN=CONNECTIONS/CN=X400 TO BECTOGO

The Event 287 shows the message is being re-routed to another server that also has an X.400 connector on it. Further events will show the message is successfully transfered to the server with the second X.400 connector. At this point the message is corrupted by the unsuccessful conversion attempt. The second server cannot process it, so it logs an event and prevents further processing of the message. The event you will see on the second server is:

   Event 200: X.400 Service Event, severity 14
   (MTA XFER-IN(12) Proc 98) 01-21-98 02:32:39pm
   Transfer-In failure, error in received APDU
   Syntax server error code mandatory absent
   Error detected at offset 892
   Internal qualifier       2913
   Node label               1msgt
   PDU dump reference       3

CAUSE

The initial message is mal-formed, causing the content conversion failure. The Exchange Server doing the content conversion then realizes it has a second X.400 connector available, and routes the message to it. The message routed is the data that failed the conversion, and is no longer a valid message.

WORKAROUND

One possible workaround is to remove the second X.400 connector from your organization.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange server, version 5.5.

A supported fix is now available, 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.