i just setup a exchange server and i can receive mail just fine but when any user tries to send a email msg (to anyone) we get the following msg.
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<domainishere.com #5.5.0 smtp;550-5.7.1 [Extrnal ip address is here] The IP you're using to send email is not authorized >
Could it be a problem with my ISP.. it is AT&T by the way..... I also tried to change the delivery settings in the SMTP virtual server and that didnt work .. What could this msg mean?