Tomcat and port 80 problem on Windows

Normally, if we want to make Tomcat to listen to port 80, we only have to change its server.xml as below,

<Connector port="80" protocol="HTTP/1.1" 
           connectionTimeout="20000" 
           URIEncoding="UTF-8"
           redirectPort="8443" />

But sometime for some reason, we can't just get it right spending a few hours on it. I used to face this problem while helping out my coworker configuring the Tomcat to use port 80. I also tried installing Apache httpd to apply it as a Reverse Proxy for Tomcat but to no avail showing "service not installed" error, after checking netstat command as described below,

I realized that port 80 wasn't free at all, and fortunately, I found out a fork on StackOverFlow suggested that some applications use port 80 in windows.

• IIS 
• World Wide Web Publishing service 
• IIS Admin Service 
• SQL Server Reporting services 
• Web Deployment Agent Service 

and we have to release it or to switch to use other port in order to get it to work.
Below is a good article which has it explained into more detail.

http://www.sitepoint.com/unblock-port-80-on-windows-run-apache/ 

Now that you know there's a few things one have to make sure before occupying the troublesome port 80 :D