How to know which port is busy or free on Windows 7? [duplicate]

Possible Duplicate:
How can I see all active connections?

I have some conflict of ports and my WampServer didn't work, so I have to know which port is used.

Is there a command line command ? or any program to monitor the ports ?

To list open ports and listening services, then from within command prompt, type

netstat -a

or

netstat -an

For more details, in command prompt type

netstat ?

Telnet attempts to connect to a server on a port

telnet <hostname> <port>

You will either connect, or not.

Simple tried and true method.

Works on Windows or Linux

To get the most information about what ports are open, what state they're in, and other relevant network information, I would suggest you download nmap. It's a free network mapper/port scanner, and by typing either nmap -v 127.0.0.1 in Command Prompt or 127.0.0.1 in the "Host" or "Target" field in the GUI counterpart (called Zenmap), you will quickly obtain any information you need about open ports on your computer.