Re: Windows 2008 connect remote port 25 problem

"Max" <> wrote in message
> I’m hoping someone here has some suggestions on this problem.
> Basicall I have a Windows 2008 server with Exchange 2007 installed.
> Emails to certains domains (but not all) get stuck in the queue and
> are never delivered. After troubleshooting the issue, I determined
> that from a command prompt on this Windows 2008 server, I could not
> successfully connect to the email domains by doing ‘telnet
> 25′. Telnet looks like it connects, but then just sits
> there with a dash on the screen. Telnet eventually closes and goes
> back to the command line. Again, this only happens with a few domains,
> the others connect fine via telnet from the command line, and of
> course Exchange delivers email to these domains just fine. I also
> thought it might be a Cisco Pix issue, but from other servers in the
> same network, but with a different public IP, I can connect to
> problematic domains by telnetting on port 25. I’ve also checked with
> tech support on these problematic domains, and they are not blocking
> our IP or filtering us in any way.
> So the issue to me seems to be somehow with Windows 2008.
> Has anyone else seen this problem or have any idea of where to look to
> resolve?
> Thanks in advance.
> Max

I have several Exchange 2007 installations on 2008 with no problems.

However, since you said you have a Pix, from what you are seeing sounds like
it is indicative of the way a Pix handles ESMTP. Therefore, if you have not
done so already, you would want to disable SMTP fixup, otherwise it will
block ESMTP, which is a Pix feature that is enabled by default as its
"Mailguard" feature, which it looks at EMSMTP as a spoof or attack.

no fixup protocol smtp 25

Read the following for more info:

E-mail and Cisco PIX firewalls

If you have an AV app on the Exchange server, make absolutely sure you’ve
exclude the Exchange folders, databases, translog folders, etc, otherwise
expect problems.

I cross-posted this to the newsgroup for
better exposure. Follow-ups (responses) will return to both newsgroups.


This posting is provided "AS-IS" with no warranties or guarantees and
confers no rights.

Please reply back to the newsgroup or forum for collaboration benefit among
responding engineers, and to help others benefit from your resolution.

Ace Fekay, MCT, MCTS Exchange, MCSE, MCSA 2003 & 2000, MCSA Messaging
Microsoft Certified Trainer

For urgent issues, please contact Microsoft PSS directly. Please check for regional support phone numbers.

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