Question : smtp;550 not local host tahoedonner.com, not a gateway

Supper irritating and intermit problem&
When some people send emails from hotmail or outlook sometimes they bounce back with a

Reporting-MTA: dns;bay0-omc2-s39.bay0.hotmail.com
Received-From-MTA: dns;BAY141-W37
Arrival-Date: Tue, 6 Nov 2007 10:00:47 -0800

Final-Recipient: rfc822;[email protected]
Action: failed
Status: 5.5.0
Diagnostic-Code: smtp;550 not local host tahoedonner.com, not a gateway

If they resend it may or may not go

Windows 2003 server with a exchange 2003 setup

Answer : smtp;550 not local host tahoedonner.com, not a gateway

That isn't an Exchange message. Therefore it is occurring elsewhere.
However I have just done an MX record lookup on the domain tahoedonner.com and have failed to find any. I use another source and I do get results. Therefore you may have issues with what ever server hots your domain.

On the connection that did work, it looks like you have a PIX or something else that is blocking or scanning the SMTP traffic. That will cause problems as well. If it is a PIX, disable fixup SMTP.

Simon.

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