Today when I start website on local IIS 7 I get the following error

Internet Information Services (IIS) Manager The process cannot access the file because it is being used by another process. (Exception from HRESULT: 0×80070020)

But I have no another webservers installed at my PC, so I am wondering what process is try to use my default 80 port. I run netstat utility to see what is happening and which process is use 80 port. And I found than its Skype. I don’t know why my Skype using this port, but after I close Skype I was able to use my IIS webserver.

And my task manager shows me what process has pid 2416

Skype, IIS 7 and port 80

But next time you reboot your PC, you face the same problem, because Skype loads before IIS 7 and start listening Port 80 and block it from another processes. To fix it you have to change settings in Skype connection window.

In Skype go to Tools->Options->Advanced->Connection
and unchecked check box “Use port 80 and 443 as alternatives for incoming connections“