The server is Exchange 2003 w/SP2
Some of the terms below may miss some people as they are military terms so if you need any help understanding them please let me know.
Here is a detailed list of troubleshooting steps that have been taken.
1. We checked our connection to our step (connection to the world), we have no transmission issues and are running on a 1544k link.
2. We restarted the Exchange services, with no results, so we restarted the server, also no results.
3. Checked our DNS on the server, as well as the firewall
4. We are able to do an nslookup and resolve any of the domains we are having trouble sending to. We also connect to the distant end exchange servers on port 25 through telnet successfully.
5. Made a Virtual Machine on our Domain controller and created a second exchange box. This exchange box is replicating the same issue.
6. We have tried pulling DNS from Unit X by putting in forwarders for their DNS, not the firewall, and we get the same results.
7. We have installed new SMTP connectors, with the same result each time.
8. No pattern to the domains in which we cannot send to, some are CONUS domains, some are theater domains to include army, centcom and socom domains.
9. Domains we can send to also seem not to have a pattern, we can send to several domains in theater as well as army.smil.mil and our shipboard domain.
I am posting this for one of the units out here that I am trying to trouble shoot with. I have personally looked at the server and I can't seem to find anything wrong as to why it will send mail to most domains but not others. I have checked www.spamhaus.org
to make sure they were not on the spam list and they were not. Thanks for the help in advance.