Well if you had to do so many reformatting, I am taking a guess that you have a COPY of XP, and since Microsoft came out with their SP2 (service pack 2), the copies of XP with registered keys, kinda of start to work erratically.
So if you have a COPY of XP, forget it, copies don't work anymore, so you might as well switch to 2000.
So if you have a COPY of XP, forget it, copies don't work anymore, so you might as well switch to 2000.