I have Exch 2003 SP1 and the domain of my DC is different than the mail domain I am trying to host on the same server. I receive the 550 5.7.1 Unable to relay message when using Outlook '03 on 2 different PC's when trying to send messages. Let me preface this in that I had it working when the new mail server was a standalone DC of rduncan.com and the original DC is no longer in production. I had installed AD on the second server and Exchange '03 to see how it would work. Exchange worked great before. I let the second server run for several days and decided to replace the original server with this new one. Here are the quick specs of the scenario - Web - original rduncan.com AD/DC and GC server, no Exchange installed Web2 - new server with AD/DC with Exchange '03 with mail.7waystosunday.com I copied the Global Catalog to Web2, demoted Web to a member server, then renamed Web2 to Web. So, now I have one server, called Web, running AD/DC and GC for rduncan.com and Exchange installed that is hosting the mail for 7waystosunday.com. The appropriate MX and DNS records are pointing correctly at my domain host and I can telnet through both ports 25 and 110 to mail.7waystosunday.com through my Netgear firewall. I configured Outlook 03 to connect to the Exchange server with an AD account that has an Exchange mailbox on the system. I can run the Outlook Account Wizard test and all 5 tests complete successfully. When I gointo a new message and try to send from this account however, it comes back immediately with the NDR and the Unable to relay message above. There's probably more to my config that you might need to know that I didn't include, so don't hestate to ask. I would eventually like to host all 8 of my domains on this one server, so if I can get it running with just the one for now, I would be very happy! Thanks in advance for the help!! Ronnie Duncan - NCS, Inc ronnie@netncs.com