What are the best ways to determine what port an application is using?

Today, user cant access a GOV application, I need to find out which port it use so that I can apply winsock setup for her.

 

Then started hunting to know which port on that application. Did little googling and found following:

 

  This is a 2 step process. First we will see ,what are the ports that are listening by different Process Ids. Next using that PID we will get the Application name.

 

Tools as below

 

The sysinternals app TCPView, which can now be found here .

 

netstat -b is a great answer, you may need to use the -a option as well.

Without -a netstat shows active connections, with -a it shows listening ports with no active clients as well.

 

Download currports from here .

It will show you which ports are open and which processes are associated with each port.

Scroll down to: Download CurrPorts