hmm panda isn't too bad at getting the difficult ones. That or there is always the time honoured tradition of whipping out the cd's and usb memory sticks and saving the documents you cannot live without then formatting the hard drive, one guaranteed fix and the best part about it if you have a restore cd (or even just access to a friends one) and the original windows xp product key you get with the computer you simply format, re-install and change the product key to your original one. Then simply place a phone call (afaik this is the only way since net validation I believe only works once) which should be free and enter in the code to activate. Believe me this manner of activation works I got the advice on it from Microsoft activation centre (from the sounds of the voices I have heard in the past based somewhere in india or bangladesh) and it has worked every time.