I am using SurfControl with ISA 2004 Server as the proxy. Ocassionally when users try to access some websites they get the following message presented to them:
Error Code:- 502 Proxy Error. The Host Server is Unreachable.
If i configure the user to bypass the proxy server and go out straight through the firewall, they can access the website concerned without any problems. This leads me to think that the ISA Server is at fault somehow, but i don't know how to resolve it.