Check if anybody is listening on a port

When we have remoting clients or windows servies we would like to know which ports are free or which programs are using or listening on a port.

We could make use of a program called TCP View from Sysinternal to see all the processes and the ports that they listen to.

Another built in way is to use the windows netstat

In order to search if there are any ports that are listening we could use

netstat -an |find "9099"

Here we are checking if anyone is listening on port 9099 if we did not get any result the ports may not be active but still registered so we are not guaranteed that these ports are free.