Hi Darren, I think you configured your RRAS to use a DHCP or a static address pool that exists in the same subnet as the internal one, so the isa server registers itself in the DNS with the new ip that obtained from the address pool. To make sure that is right you can ping isa server from the internal network (Ping "isa server name") and note the resulting ip. To solve this probelm you can edited the hosts file on each computer and add the internal isa server ip and its name or assign a new adress pool that lies in a different subnet from the internal one. Tom, I'm note sure this problem is due to the isa server is configured as DNS and Domain controller only, because i have encountered the same problem while i have isa server and a seperate DNS and domain controller. Thanks, Amr Omar IT Manager Siliconexpert Tech.