I am in the process of upgrading my network to Win2k native mode with exchange 2000. I want my exchange server in the private network and have configured a protocol rule named "Mail wizard rule - SMTP Server" with the wizard. When I do netstat -an on the ISA server, I see no "listening"on port 25. Currently, I have my private network exchange server communicating with a front end exchange server(no mailboxes). There is no firewall between the servers, as I used the front end server while I built the exchange server in the private network. I subsequently moved the mailboxes from the front end server back to the internal exchange server. Now I want to decommission the front end server and just run my private exchange server from behind the ISA server. I expect the the mail wizard rule using SMTP Server protocol should open ISA so that other mail servers can send email messages destined for my domain. I cannot determine what else I need to do to get my internal exchange server to accept inbound smtp from other mail servers. Any advice is appreciated. Thanks, Rich M