IIS 7 returns 404 for all requests

Question

I have a default website and 2 applications underneath it. One is a WCF service on "http,net.tcp". The other is an asp.net site.

When I browse to the service, static files, the asp.net site or the default website I get a blank 404 response. The raw response in fiddler is "HTTP/1.0 404 Not Found"

I've tried reinstalling IIS. I thought it might be the handlers so I've had a look at the list but don't see any obvious issues.

(I can still connect to the service 'dsxwebservice' with tcp, and this issue has only been present for a few days, probably triggered by some change I've made to the configuration / install)

Answer 1

A common reason for this issue is wrong configuration such as invalid hostname in configuring the binding.
Check the following:
1. That the hostname used is the binding configuration is correct
2. That this hostname resolves to the IP address of your server correctly (ping or telnet on port 80 to confirm)
3. You can also add a binding on all IP addresses without a hostname on a different port (say 8080) then browse to localhost:8080 to see if all other configurations are correct
4. Another check is to run aspnet_regiis

Answer 2

In my case, Skype was interfering with IIS handling of requests on port 80. Changed skype settings and all fine now.