I am running ISA Server on a Windows 2000 Server. I am running Windows 2000 Terminal Services for my users. They connect to the Internet through ISA. When users attempt to connect to a particular site that has a Java Applet that allows them to login to an AS/400 computer, the users get a an tcp/ip error. I talked with the people running the web site and they said we need to enable port 43856. I tried to create a new protocol definition in which I created port 43856 as a secondary connection (the primary being port 80). It still doesn't work. I can, however connect to the web site not using the isa server so I know it isn't a router issue. Any suggestions would be greatly appreciated.