Email bounce back

[A]

Two people in our office sent email to a particular email address. The 1st
senders email went through while the 2nd bounced with the following message:

The following recipient(s) could not be reached:

(e-mail address removed) on 4/12/2007 11:56 AM

There was a SMTP communication problem with the recipient's
email server. Please contact your system administrator.

<servername.domain.com #5.5.0 smtp;502 Command is locally
disabled>

We are running an Microsoft Exchange Server 2003 with Static IP. The email
was sent to a large ISP (residential) who probably recv's a dynamic IP
address.

Thanks.

 

[K. Orland]

Have a look at the SMTP protocol logs and find out what command it is
that's unacceptable. There are quite a few broken SMTP servers out
there that do silly things like advertise an ESMTP keyword and then
not accept it.

You may want to post to an Exchange newsgroup instead, it's doubtful this is
an Outlook issue.