Way To Find Open Ports(windows)

1) Download Nmap nmap-5.61TEST4.tar.bz2 For windows from http://nmap.org/download.html
2) Install it
3) After finishing installation u'll find Nmap icon on your desktop, right click, open file location. Then copy the whole location for the app from the address bar
Eg: C:\Program Files\Nmap
4) Now open cmd, type in cd C:\Program Files\Nmap and hit enter
5) Once you are into nmap folder type in "nmap hostname"
Eg: nmap rentmychest.com
6)Display would be something like this

Starting Nmap 5.61TEST4 ( http://nmap.org ) at 2012-01-10 19:57 ******** Standard T
ime
Nmap scan report for rentmychest.com (69.167.141.223)
Host is up (0.31s latency).
Not shown: 994 filtered ports
PORT STATE SERVICE
21/tcp open ftp
22/tcp open ssh
53/tcp open domain
80/tcp open http
443/tcp open https
3306/tcp open mysql

Nmap done: 1 IP address (1 host up) scanned in 28.67 seconds
7) There we go. We have open got the list of open ports for the desired host
Hope i was helpful:)