Open port on router for peer to peer dow...

The port you need to open depends on the specific application you're using.

Go to the website of the application you're using and search their support area for port settings or firewall configuration settings.

Some applications have a user forum where you can find the answer as to what ports are required to be open.

Here's an example of the ports that would need to be open for Limewire: (this does not mean these are the ports that need to be open in your case)

In LW tools > options > advanced > firewall config. Change LW's listening port to 65000 (or try any ports in the range of 49152 - 65535) > apply > ok. If you have port forwarding set up for a modem/router, you'll need to change the port forwarded to match LW's new listening port. If you have a specific port number allowed thru a software firewall, make sure that you allow LW's new port number.