I have windows XP Professional. Spybot was working just fine then 1 day it wasn't. I can D/L latest immunizations (so I can update), but when I do a check for problems it starts, says it is scanning ... but isn't. There is no green bar along the bottom, and the hard drive icon on my computer is showing no activity... and eventually when I stop it it freezes and I have to ctrl-alt delete to stop it's process. I have removed it and reinstalled and also run it in safe mode. None of it helped.