X400: Nondelivery Reports to Incorrect User by Softswitch EMX

The information in this article applies to:

• Microsoft Mail Gateway to X.400, version 3.2

SYMPTOMS

Read receipts and delivery notifications may be sent to the incorrect address by Softswitch EMX if the unique identifier the Microsoft Mail Gateway to X.400 places on each message is not unique.

CAUSE

The X400GATE.EXE program uses the message protocol data unit (MPDU) identifier, an IA5 string that includes the Coordinated Universal Time (UTC time) as the unique identifier; however, this MPDU is not unique if the gateway ends the translation of two outgoing X.400 messages in the same second.

RESOLUTION

The X.400 gateway has been modified to ensure that the time used is always unique. The last time used is now stored and compared to the time retrieved on the next message. If they are the same, the program will continue to ask for a time until it receives a different time than the one stored. It then stores this new time value, for comparison on the next message.

STATUS

Microsoft has confirmed this to be a problem in versions 3.0 and 3.2 of Microsoft Mail Gateway to X.400. This problem was corrected in X400GATE.EXE version 3.2.14. If you do not have version 3.2.14 (or later), you can find X400GA.EXE, a self-extracting file, from the Microsoft Software Library (MSL) on the following services:

You can find X400GA.EXE (size: 203636 bytes) 
                       , a self-extracting file, on the following

• Microsoft's World Wide Web Site on the Internet

        On the www.microsoft.com home page, click the Support icon.
        Click Knowledge Base, and select the product.
        Enter kbfile X400GA.EXE (size: 203636 bytes) 
                               , and click GO!
        Open the article, and click the button to download the file.
  
  

• Internet (anonymous FTP)

        ftp ftp.microsoft.com
        Change to the Softlib/Mslfiles folder.
        Get X400GA.EXE (size: 203636 bytes) 
  

• The Microsoft Network

        On the Edit menu, click Go To, and then click Other Location.
        Type "mssupport" (without the quotation marks).
        Double-click the MS Software Library icon.
        Find the appropriate product area.
        Locate and Download X400GA.EXE.
  

• Microsoft Download Service (MSDL)

        Dial (206) 936-6735 to connect to MSDL
        Download X400GA.EXE (size: 203636 bytes) 
  

   ARTICLE-ID: Q119591
   TITLE     : How to Obtain Microsoft Support Files from Online
               Services

MORE INFORMATION

If a Microsoft Mail Windows client user sends a Mail message to the UNIX user with Delivery Report and Read Reciept, this bug causes a critical error on the Softswitch MTA (EMX) side which operates an X.400 backbone message switch. If a message is forwarded by the EMX, it stores the message and, if a notification is requested by the sender, waits for the report

If the requested report arrives, the EMX searches the corresponding original message according to the specified MPDU ID. EMX takes the originator address of the original message and submits the report to that address. Because the MPDUs of the original messages are not unique, the EMX often associates a report to the wrong original message, and thus submits the report to a different user.