SMTP: Explanation of FROM Field wit (98067)



The information in this article applies to:

  • Microsoft Mail Gateway to SMTP 3.0
  • Microsoft Mail Gateway to SMTP 2.1

This article was previously published under Q98067

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


Modification Type:MajorLast Reviewed:2/24/2004
Keywords:KB98067