80 port is occupied by the process of solving one example

A friend of mine contacted me today, saying that the website on the server could not be opened. It is suspected that port 80 was occupied, but the program could not be found. So the remote desktop on the server, the solution process is as follows:

1, habitually first view the event log, nothing.

2, tasklist to see if there is an abnormal program, no abnormalities found.

3, netstat view port, found that 80 is not used.

After these three aspects of the search, can only be attributed to IIS itself, the preferred way to solve their own problems is to reinstall IIS, so open the add and remove program, an unexpected discovery, the computer is installed An IIS7.5 Express, then the normal and the website can not be accessed can explain, are Microsoft's IIS, 2 versions of the conflict, so first uninstalled IIS7.5 Express, restart IIS, unresolved. Restart the server and open the website.

This time because IIS7.5 Express occupies 80, and because it is IIS, no events are found in the event log, task management, and port.