SMTP connection problem

[Wodill]

We have an Exchange 2003 system that has been in production since August 2004. Now one of my users is getting an NDR message when sending to a specific domain.

The error message is
"There was a SMTP communcation problem with the recipient's email server. Please contact your system administrator. <receipient's email server #5.5.0 X-Unix;69>

When I looked up the error in Microsoft, it stated to try to telnet using port 25 to the mail server. I was able to do this successfully so I'm not sure what the problem could be.

 

[gerbieIT]

Is it only one user?

 

[Wodill]

Yes, it is so far for this domain. We have confirmed that is the proper email address.

I also telnetted to their mail server via port 25
220 [receipentmailservername] ESMTP Sendmail 8.12.10/8.11.1; Thu, 4 Nov 2004 14:07:02
-0600 (CST)
helo [mymailservername]
250 [theirservername] Hello [x.x.x.x], pleased to meet you
mail from:myaddress@mydomain
250 2.1.0 myaddress@mydomain... Sender ok
rcpt to:user@theirdomain
250 2.1.5 user@theirdomain... Recipient ok