Checking IIS and see that the Default Site (Appserver) will not start. Try to start produces an error.

Error is shown in IIS as The process cannot access the file because it is being used by another process (Exception from HSRESULT: 0x80070020)

Also in Windows System logs as Error 1004 – IIS-W3SVC service did not register URL with prefix “http://*.*:80”

To check which application is using the port (in this case Port 80)

In the Command Prompt type

netstat -aon | find ":80"

The output would be similar to

TCP    0.0.0.0:80            0.0.0.0:0              LISTENING       3604 

Now open Task Manager and select right click on the columns of the processes running and select PID (Process ID). Then run through the processes and see which one is using the ID 3604 (in this case it was Apache).

https://stackoverflow.com/questions/24021071/unable-to-start-web-site-iis-hresult-0x80070020