I downloaded files using the Download Accelator Plus software (DAP) and the files were stored in My DAP Downloads folder. When I finished downloading, I moved the files into another fresh directory. It were big files and suddenly there was an error and the computer hang. I switched the computer off and on, and there was the error, and the message said that the disk may not be formatted. Even I pointed to the drive of the harddisk and right-clicked, it said so. I need a help to fix the problem.