troubleshooting Question

RDNS Failed on emails sent using a mail sender from client machines

Avatar of Clement P
Clement PFlag for United Kingdom of Great Britain and Northern Ireland asked on
Email ClientsExchangeWindows Server 2003
4 Comments1 Solution1098 ViewsLast Modified:
We use exchange server 2003 to send our emails, and the same is configured to use a message labs as a smart host.

Emails are going fine when they are sent from outlook (connected to exchange server), however when we use a mailing software from client machines we get RDNS failed error on the emails.

Received: from ([] RDNS failed) by with Microsoft SMTPSVC(6.0.3790.4675); Mon, 13 Feb 2012 11:25:37 +0000
From: "Test User" <> "

And a bit about our DNS Settings,
our mail server internal ip is
external ip for the mail server has rdns as
Our browsing IP has RDNS as

How do i get the RDNS failed sorted with our settings as above??

Many thanks for your help

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