CurrPorts from Nirsoft is a tiny application that displays the list of all currently opened TCP/IP and UDP ports on your computer and gives information about the process that opened the port , including the process name, full path of the process, version information of the process, the time that the process was created, and the user that created it.
This program automatically marks suspicious TCP/UDP ports owned by unidentified applications with pink color. So that you can easily veryfy and close unwanted TCP connections, kill the process that opened the ports. [You can also do these without software, by the command ‘netstat –ano’ and with Task manager]
Here is a simple example to find out an open port and the process. Just unzip CurrPorts and run it (no installation required). This will list all currently active network connections, process name and path and other information. Look under ‘Remote address’, if the value of the field is ‘0.0.0.0:0’, then it means the port is closed. If you find an IP address instead of 0.0.0.0.0., you need to verify the process that opened that port. If it is an unidentified program you can close the port and kill the process by right clicking on it.