External Email Problems

[beammie]

Exchange 2000 - Windows Server 2000 SP3 - WatchGuard Firebox 700.

Users are complaining that about 1 out of 10 external emails are being bounced back to the sender. Senders are getting bounce backs stating that there is an SMTP error and the mailboxes do not exist. However, they can send the same messages immediately to another user on our system with no problems. Also, if the sender tries to send the message again at a later time, the message goes through.

These messages are from different domains and the email address the senders are using are correct.

Does anyone know what would be causing this? Would this be an issue with our Exchange Server, ISP, or Firebox?

 

[Marcs41]

Post the errorcode from the SMTP error, that would (maybe) tell us more.

Marc
_{If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
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[beammie]

There are a few messages that the sender is getting:

There was a SMTP communication problem with the receiptent's email server. Please contact your systems administrator. #5.5.0 smtp; 521 Server does not accept mail.

521 server does not accept mail - permanent fatal errors

Message was rejected by domain - server does not accept mail

 

[Marcs41]

Check you Event log for errors too arounf that time, send one more mail to have a timestamp

See also

http://www.faqs.org/rfcs/rfc1846.html

Marc
_{If 'something' 'somewhere' gives 'some' error, expect random guesses or no replies at all. Please specify details.
Free Tip: The F1 Key does NOT destroy your PC!}
How Do I Get Great Answers To my Tek-Tips Questions? See faq222-2244