Publishing a web site located on the ISA Server entails some special problems you must address before you begin publishing. By default, IIS wants to use Port 80 to listen for inbound web requests. However, since the ISA Server’s Web Proxy service uses Port 80 to Listen for inbound web requests, you cannot have both the ISA Server and the IIS WWW Service both listening on the same port.
ISA Server allows you to make internal resources, such a web servers, email servers and FTP servers, available to Internet users. This process of making internal services available to users on an external network is called “Publishing”. When you Publish a service on your internal, private network, you allows selective access to external users.
If you are just getting started with ISA Server you might find that its hard to tell where the place is to start. One place you could start is by using the Getting Started Wizard. You can access the Wizard by opening the ISA Management console and clicking the topmost node in the left pane. Be sure that you have Taskpad view enabled by right clicking on an object in the left pane, then going to View and then click on Taskpad.