XCON: NDR from Malformed Message Not Received (179837)

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
				

Note: The connector names and target entity names will be different for servers.

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
				

From looking at the Protocol Data Units (PDUs) saved in the BF*.log files, (in this case PDU reference 3), you will notice that the data is cut off at offset 892. The sending server's PDU is exactly the same. This is the message after it has been corrupted by an unsuccessful conversion attempt.