I currently have a home network for a small business and testing. How do I point the DYNDNS IP address from the cable modem to the Mail server mail.tricityteks.com (DNS setup correctly). I have the following: 1. Cable modem connected to router 2. DYNDNS IP Cable modem 10.x.x.254 3. Router serves and internal network 172.x.x.254 4. Server off of router at 172.x.x.10 (external access NIC) going to a switch where all other devices are connected to Intranet at 192.x.x.10 (internal NIC) There is an ISA 2004 firewall on the server. (SBS 2003 server) The mail server (mail.domain.com) points only to the cable modem dynamic IP 10.x.x.254 ---> I need it to point to the server in the network using the ip range 172.x.x.10. This is so I can setup the mail server to send and receive mail. :cry: How do I accomplish this?