My Gateway desktop, running XP, was freezing after startup. I found advise somewhere on the web to try cleaning the fan, so I did. After putting the computer back together, it didn't freeze up anymore, but my avast found several malware viruses called rootkit? I moved them to the chest as recommended, and later deleted them.....maybe I shouldn't have done that. But now even though my printer is connected, computer tells me it's not; even though speakers are connected, computer tells me they aren't; even though internet is connected, computer tells me it's not; and last night, I also discovered that none of the USB ports are being recognized. And one more problem, I cannot load it into Safe Mode.