diem2412 how to disable loopback adapter
FIND the loop back adapter and right click disable.
if you dont know how to find your loopback adapter try this: (not sure if this works for windows XP) go to control panel then network connections (Control Panel\Network Connections in your browsing bar at top of folders should work) you will see a number of files look for the one which says "local area connection (a number)" and in small writing below it "microsoft loopback adapter" inbetween those is the word "enabled" or "disabled" right click on that file and choose the option you want to do

. you may want to make a short cut on your desktop to it so it is easy to turn on and off.