Im having issues with incoming mail via ISA 2006, I have tried to publish our SMTP server however mail cannot be delivered to the exchange server via ISA.
The ISA server is setup in a 2NIC config Internal--ISA--Router--Ine
The external NIC has a manually assigned address from the router subnet, however microsoft states that when specifiying the external ip in the publishing wizard I should have the MX record IP (ie our static external ip) but this is not an option as the only ip I can select is the ip of manually assigned router ip on the external nic.
If I select in the networks tab external selected ip as all ip addresses is still get through. On the monitoring I cannot see any traffic coming through or being denied on port 25, however when i use mxtoolbox.com i get the following error"No connection could be made because the target machine actively refused it" I know the mx record is setup correctly so thats not an issue. Any ideas on how to get this working?
Please not I have already walked through the following to double check my config and everything is fine other than the external static ip.