Bizarre - Can't find website folders on server

We have an external site with a specific port configured for people to access the “portal”, in the form http://<ip address>:7778 (i.e using port 7778). The port is set on our router to pass through to an internal IP address, which is the IP address of a Windows 2000 server on the LAN.

Basically I’m trying to find out where exactly the code is for this portal site- you’d have thought it would be sitting in IIS on the Windows 2000 server but it isn’t. In fact the folders and files that I see in the source code don’t even seem to be on that server at all. The portal site seems to have been set up using Oracle but I can’t see any of the files or folders within the Oracle installation on the server.

And yet looking at the source code I see the links clearly point to http://<internal windows 2000 server>/foldername/foldername/filename. I guess these links must be being generated somehow and aren’t “real” links, but how do I find out where the portal site is actually located?

The router just sends requests through to the internal 2000 server so I can only assume that somehow that server is forwarding anything coming in on port 7778 to another server? But how can I find out which one?

Any ideas as this is just bizarre!