I was having problems booting up my Windows XP system when someone on EE suggested that I unplug all USB connections. I did that and that worked. However...,.One of the USB connections is an external hard drive. When I reconnect it, the system freezes up and the hard drive is not recognized. Is there something I can do short of taking this into the PC shop again to get the hard drive recognized? I tried to find the disk that came with it but of course I can't find it.