If you built your own network using a broadband router, the router will automatically prevent any P2P file sharing program (eMule, Shareaza, etc) from working correctly on your network: it will either get a “low ID” or will be shown as “firewalled”. As a consequence you will get lower transfer rates and also won’t be able to initiate file downloading from users that are also “firewalled”. In this tutorial we will teach you how to configure your router to correctly allow P2P file sharing programs to work.

This problem happens because P2P programs use non-standard ports to work. Since broadband routers work as a firewall, they block all connections using non-standard ports. So in theory it would be just a matter of “opening” the ports that your P2P program uses on your broadband router control panel to solve this issue. However, it isn’t that simple. Usually by simply “opening” ports on your firewall programs have access to servers on the Internet using these ports, but it doesn’t allow other computers on the Internet to have access to your PC. In other words, while the firewall will allow outgoing connections, it will still operational, blocking incoming connections. Keep in mind that when using P2P programs your computer will act as a server, delivering files (and parts of incomplete files) to other users.

On this tutorial we will use eMule as our example. The basic idea shown on this tutorial is exactly the same for other programs; the only different thing will be the exact location of the options we need to change on the program. You will be able to adapt this tutorial to other programs very easily.

Let’s first take a look at the problem. After downloading and installing eMule on our PC we hit “Connect” and we got a “low ID” status, as shown in Figure 1 (follow the red arrow). The correct would be getting a “high ID” status (for security reasons we removed our IP address from this screenshot).

eMuleFigure 1: Getting a low ID with eMule.

To test your connection, go to Options, Connection and click on Test Ports. This will test your connection to check if people on the Internet is being able to access files located in your computer. As we had this low ID problem, the result wouldn’t be different than the one shown in Figure 2 (once again we removed our IP address from this screenshot for security reasons).

eMule Port TestFigure 2: Connection test failed.

The goal of our tutorial is to make your computer to pass this test, thus giving you a high ID on eMule.

The first thing we should do is to reconfigure eMule to use a different set of TCP/IP ports. On the eMule version we installed it was using ports 19034 for TCP protocol and 17157 for UDP protocol. You need to change that to 4660 for TCP protocol and 4670 for UDP protocol. This is done on Options, Connection. In Figure 3, you can see how our eMule was configured and then in Figure 4 you can see eMule correctly configured. Don’t forget to click on “Apply” after changing this configuration. Exit eMule.

eMule Port ConfigurationFigure 3: Ports that our eMule version was using.

eMule PortsFigure 4: eMule correctly configured.

If you are using a different P2P program, we recommend you to enter its configuration menu and change its default TCP and UDP ports to the numbers we suggested, in order to make it easier to follow our tutorial.

Now you need to configure Windows XP’s internal firewall.

Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.