I'm have just started a contract on a domain with 2 2003 DC's and a stand alone 2003 exchange server behind a sonic firewall.
Problem is that some one prior to me setup the mx record from their web domain host to point at the exchange server which caused 2 main problems.
1. They had many problems mostly due to ISP dropping connection and mail being redirected to the domain host mail servers. Therefore they had mail on the exchange and the mail host servers. I had the domain host to change the mx record back and currently have all the client setup via outlook pop3 mail.
2. I'm getting weird smtp errors in the App. log which I am going to post in a little bit when I get over there. It seems like they setup different smtp virtual servers and moved away from the MS defualt. I am not sure how to get rid of those and just use the MS defualt setup to route outgoing mail via DNS.
So to remedy situation 1 I install MapiLabs Native Pop3 connector on exchange box and setup a test client to try it out.
I'm not receiving any incoming mail and I know port 110 is open on the firewall because all the pop3 outlook client are recieving fine.
When I get there in about an hour I'm going to post the DNS error and the native pop3 log for review.