Hi, I have a ISA 2004 SP2 installed in an environment with two DC's installed in it and have configure the firewall to use AD authentication. The problem I am getting is that when I re-boot one of the domain controllers we are no longer able to get out to the internet, the firewall requests a username and password, with the other DC being available I don't understand why this is happening. Any ideas, have I missed something in my setup? Thanks Andy