When I send emails out, by looking at the headers I see that the name of the server shows instead of the mx record. This is what the header shows: Received: from file4.F3.local (mx.marinedepot.com [206.40.201.234]) And Received: from file4.F3.local ([192.168.1.20]) by file4.F3.local -------- 192.168.1.20 is the internal server IP address and the 206.40.201.234 is our mx record. My question is how can I change the file4.f3.local address to mx.marinedepot.com or anything else for that matter.

Check your SMTP virtual server settings, but generally its OK to leave it as you've got it.

More importantly you will want to set the SMTP outbound name to match the external IP's reverse dns lookup address. It appears yours is setup correctly, 206.40.201.234 does indeed show a reverse name of mx.marinedepot.com.In Exchange (2003), open up the SMTP protocol properties and under the DELIVERY tab click on ADVANCED and change the "Fully-quilified domain name" to mx.marinedepot.comAndy