I have Exchange 2003 SP2 installed on Win 2003 R2 SP2 server which is also acting as domain controller for our small organization.
Another Server with Win 2003 R2 SP2 have ISA 2006 installed for internet access. I will be getting real IP addresses in a day or two from my ISP and my plan is to use our email server for sending/receiving emails from outside. Uptill now Exchange was serving for local emails and for outside emails users were also having POP account configured in their outlook 2007.
To be honest I am first time trying to do this and have no idea how to begin once I have real IP addresses from ISP. I request from experts if any one can please share details step by step guide to perform this task. i heard something about MX records and A record but could not understand it.