I have some bad news. From the
BASIC HDD FAQ
07. My hard drive has developed Bad sectors! What should i do?
Firstly backup all your critical data fast! Then you have a choice. You can reformat the drive using the manufacturers diagnostic utility which marks bad sectors as bad and no longer uses them to store data. This however does not prevent further bad sectors from developing. And its almost guaranteed that you will get more at a later date. The better solution is to replace the drive, or send it back (RMA it) if it is still under warantee.