I'm posting here because I can't determine whether this is an "apps" or "networking" problem.
Using Outlook Express (and also happened when using Outlook 203) on a home computer, running XP, non-networked, to send e-mail, I sometimes encounter this error when sending messages:
"The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was '[name]@ca.ibm.com'. Subject '[title]', Account: 'pop.[our domain].org', Server: 'mail.[our domain].org', Protocol: SMTP, Server Response: '553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)', Port: 25, Secure(SSL): No, Server Error: 553, Error Number: 0x800CCC79. "
I am 99% sure this is not actually coming back from the recipient because I send to this address and to several others "@ca.ibm.com" regularly with no problem. Also, the error seems to be fairly random--I can get this message sending to other well-used addresses also, equally inconsistently.
When I first got this, I called my new hosting provider, thinking it was triggered by a recent hosting change. They said they recognized the problem, disavowed it, and recommended I switch to Outlook Express from Outlook. So I switched, but this is still happening. Sometimes I can get around it by shutting down and re-opening OExp, and doing a new Send/Receive, THEN trying to resend the failed message (note, the message does not remain in the Outbox. It is listed in "Sent", so I have to drag it back to the Outbox to resend).
All other postings I can find on this error message point to Exchange Server, which I'm not running. Is there some undead vestige of Exchange Server embedded in Outlook and Outlook Express? The only other variable I can think of that has been recently introduced is SP2 for XP.
Thanks for any ideas,