Since you are reading this guide, I'm going to assume that you have Bit Tornado installed. Open up Bit Tornado.
Close to the top you will see a Prefs link. Go ahead and click that link now.
The Port Range box defines the ports that Bit Tornado will use. These are the ports that you need to open to your computer. Bit Tornado does not need the full 50,000 ports that come predefined. Go ahead and uncheck the Random checkbox. Enter 10000 into the From box, and enter 10010 into the To box. If you expect to download more than 10 files at the same time, then you should make this range of ports larger.
On this page there is a UPNP Port opening drop down box. Open it up and set that box to disabled. We are not going to use UPNP to open our ports. Now go find your router on our routers page, and open the port range you set above.
Click the Security Center link near the bottom left of the page.
Click the Windows Firewall link near the bottom right of the page.
Remove the checkmark from the Don't allow exceptions checkbox.
We will list a series of lines here that will show you exactly how to setup Windows XP Firewall's firewall for BitTornado. Go ahead and enter the settings shown below into the Add Port menu.
You should see another page of settings below that need to be added to Windows XP Firewall. Open up a new Add Port page and enter those settings.