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Q107087: SMTP: Err Msg: Warning No Return Path

Article: Q107087
Product(s): Microsoft Mail For PC Networks
Version(s): MS-DOS:2.1,3.0
Operating System(s): 
Keyword(s): 
Last Modified: 07-NOV-1999

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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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SYMPTOMS
========

The Microsoft Mail Gateway to SMTP displays this warning:

  WARNING No return path
  [tx] 250 Sender OK

CAUSE
=====

The name provided in the "mail from" received by the sending host is incomplete
or contains a null value:

  [rx] mail from:<>

RESOLUTION
==========

None necessary: this message is informational only and requires no action by the
Mail Administrator. The Gateway continues to process mail.

MORE INFORMATION
================

The example below shows an address without a beginning "<" and an ending
">". This log file was created using the undocumented -CD option which tells
the Gateway to display debug information.

  >Incoming SMTP connection from [192.245.59.139]
  [tx] 220 All set, fire away
  [rx] hello fake.host.com
  [tx] 250 Hi there, pleased to meet you
  [rx] mail from:jdoe
  >WARNING No return path
  [tx] 250 Sender OK

Additional query words: 2.10 3.00 2.1 3.0 warning

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

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