I have a computer here that won't boot correctly. There are 2 hard drives, and the user said that he attempted to run a scan after the machine began to run slow, and then it wouldn't boot. I have stripped out the 2nd HD and set the jumpers back on the main drive. When attempting to boot the machine it starts to load the OS then shuts down. When it shuts down I get a A: drive error press F1 to continue....,doing this then sends it into the same loop over and over........any insight to this?