We have an outside location that has recently been connected to the
Internet via an ISP. Their email accounts are configured to access
out corpoarte Exchange server via POP3.
They can send/receive internal email and can only receive external
email. When they try to send external email they receive the
following email message in their inbox:
"The message could not be sent because one of the recipients was
rejected by the server. The rejected email address was
'name.company.com', Protocol: SMTP, Server Response: '553 Requested
action not taken: mailbox name not allowed', Port: ###, ....Server
I believe this is an authenication issue, because when I uncheck
"Hosts and clients that successfully authenicate" in the routing
section, they can send external email. But I don't want to leave this
unchecked for obvious reasons.
How to correct the problem to have them be able to send external
email? What am I overlooking?
Any help would be greatly appreciated.