i was upgrading to a newer build but it was not a bootable cd so i clicked the auto run icon not noticing that my anti virus was off the sys instantly shut down when i restarted it, it restart right before it reaches the welcome screen i would have just formated it but i have some important files so i went and install and older xp sp2 on the same partition so i can use the pc. Oh!!!! i also tried booting in safe mode and that doesn't work either