I don't use Windows XP anymore but I think how I remember how this works
Anyway this probably won't be of much help but just try it anyway
Go to Start and click on run
In the box type cmd
A window should come up, in that type ipconfig then press return
Your router info stuff will come up, and look at the default gateway and make sure you have the numbers on the default gateway correct. It could be one number mistake messing it up
That probably won't help at all, but you never know unless you try
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