Last week I installed ISA server on an old machine. I configured clients as SecureNAT. This worked great, everyone had web access. This week, the ISA machines hardware started to fail on me, so I installed ISA on a new machine, with IDENTICAL settings (but obviously different ip's). Now I have both ISA servers using the same enterprise policy in the same array, so why is it that once I change the clients gateway to the internal IP of the NEWER ISA computer, they do not have any internet access? :/