DOCUMENT:Q98067  05-NOV-1999  [pcmail]
TITLE   :SMTP: Explanation of FROM Field wit
PRODUCT :Microsoft Mail For PC Networks
PROD/VER:MS-DOS:2.1,3.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Mail Gateway to SMTP, versions 2.1, 3.0 
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SUMMARY
=======

If a message cannot be successfully delivered, the Microsoft Mail Gateway to
SMTP or Microsoft Mail may generate a message from
"Network/Postoffice/Postmaster," advising the sender of a problem.

These messages can sometimes get bounced back and forth between Microsoft Mail
and the SMTP environment if the sender or recipient names are invalid. To stop
this bouncing phenomenon, (also called looping or ping-pong) the SMTP Gateway
replaces "Network/Postoffice/Postmaster" with "<>" (Greater- than and
Less-than signs).

The message is not returned to the Microsoft gateway because the SMTP host does
not have a valid address to send the mail message back to; it is sent to the
administrator for the Microsoft gateway.

Example
-------

OUTGOING MESSAGES:

If an outgoing message is from:

   Network/Postoffice/Postmaster

The SMTP Gateway replaced it with:

   <>

INCOMING MESSAGES:

If an incoming message is from:

   <>

The SMTP Gateway replaced it with:

   Network/Postoffice/Postmaster

Additional query words: 3.00 2.10

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Keywords          :  
Technology        : kbMailSearch kbMailGateSearch kbZNotKeyword3 kbMailGateSMTP300 kbMailGateSMTP210
Version           : MS-DOS:2.1,3.0

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