After installing ISA server and using the mail server wizard, my exchange server no longer send mail to the outside world. I can recieve mail, but it will not send. All I did was replace our current GnatBox firewall with ISA. The mail worked before, and I didn't change anything. The error is as follows, An internal DNS error caused a failure to find the remote server. I can however resolve domain names from my exchange box, so this to me is weird. Any help? Dieter