[cobalt-developers] Errors sending email

["Mikes FNP" <mikes@xxxxxxxxxxxxxxxx>]

When sending email from a client to the server, I am receiving information
from my clients that this failure occurs on a regular basis.  The messages
are as follows:

The message could not be sent because one of the recipients was rejected by
the server.  Server Response '554.5.0.0
rewrite:excessive recursion (max 50), ruleset canonify', (Account:
'www.urlname.net', SMTP Server: 'www.urlname.net',
Error Number: 0x800ccc79).

The message could not be sent because one of the recipients was rejected by
the server. The rejected e-mail address was
'cobalt-developers@xxxxxxxxxxxxxxx'. Subject 'Problems Sending Email',
Account: 'Account Name', Server: 'urlname.com', Protocol: SMTP, Server
Response: '550 5.7.1 <cobalt-developers@xxxxxxxxxxxxxxx>... Relaying denied.
Please check your mail first.', Port: 25, Secure(SSL): No, Server Error:
550, Error Number: 0x800CCC79


Any ideas?

Mike