Raven Shield Rainbow Six "oldy"

I'm trying to host some maps for some friends and they keep getting "NO SERVER RESPONSE" When they are trying to access my PC The server name show's up in the server list, The XP firewall is disabled,I have all the required ports open in the Lynksys WRT160n router, I use AVG free version anti virus I uninstall any spy ware software ,I set up for static IP I modified the server INI to NAT=True still no go, anybody PLEASE I need some help!!!