Alternatively, you might just have hit a bad set of sectors on your hard drive. If possible run disk-check program to identify them and clear them up. Also, run a de-fragmentation program. A couple of years ago I experienced similar problems. In my case it turned out that the HD was on its way out, and needed to be replaced. Alas, I found that out too late, and a lot of stuff that I had on the failing disk was lost. Keep a CAREFUL check on the integrity of your hard drive! Cheers, Diolma