Question: I've installed TFS 2008, but I can't seem to access the server. When I try to connect to it in Visual Studio, I can't. If I try by browser on a remote PC, I get a generic page cannot be displayed. On the server, I get a 403. Nothing was touched in IIS and the service is running as a Network Service. Any ideas?

Answer: 
Turns out the time and date on my computer was not "close enough" to the time and date on the tfs server. Changed my system clock setting and problem went away.
What happens if you send a simple HTTP request to the server directly?

ie:
telnet 8080 [enter]
GET / HTTP/1.1[enter]
[enter]
[enter]

That might give a hint about whether IIS is actually serving anything. If you can do that on the server, what about from a different machine? If the results are different a good guess is there are some security/firewall issues somewhere. HTH a little.