That's normally bad RAM, NIC or Driver.
Bad Driver;Reinstall (find which one to reinstall using Hardware Explorer).
If it's XP check the recovery options - it's possible you could use them... if you remember when the problem first happened.
Hardware;Try removing a stick of ram at the time and try to replicate the error. If you cant then the stick you have in your hand is bad.
If that doesn't work then remove the NIC - it's possible that could be causing it as well.
Laptop or desktop?
Off to bed - back tomorrow.
