I just set up a new alias for a domain that is 36 letters long. (in case that matters, somehow.)

I receive the following message back when I try to mail the account...

----- The following addresses had permanent fatal errors -----
<sales@36-letter-domain.com>
(reason: system config error)

553 5.3.5 www.36-letter-domain.com. config error: mail loops back to me (MX problem?)
554 5.3.5 <sales@36-letter-domain.com>... Local configuration error

-------------------------------

The MX records appear to be right, according to many other domains that work fine.

Anyone know what the problem is, where I can look to find the problem, or what I might do to fix it?

Help is very much appreciated.

Thanks!

I reinstalled the entire site and the immediate problem is fixed. I'm still interested in knowing how I might fix such a problem without reinstalling the entire site.

Thanks.