|"showing bad sector"|
Your hard drive is probably in the process of failing.
Check your hard drive with the manufacturer's diagnostics.
See the latter part of response 1 in this:
If you don't have a floppy drive, you can get a CD image diagnostic utility from most hard drive manufacturer's web sites, but obviously you would need to make a burned CD, preferably a CD-R for best compatibility, on another computer if you need to.
Seagate's Seatools will test (almost) any brand of hard drive.
Do the long test.
The bootable Dos versions of SeaTools can be used even if Windows is not working properly.
If the hard drive itself tests okay, any data problems found can be fixed, one way or another.
If the hard drive itself DOES NOT test as okay,
- if the SeaTools long test finds a small number of LBA errors, you can have it zero fill the drive to see if it can fix the problems.
However. doing that wipes all data from the hard drive
- if the SeaTools long test finds more than 99 errors it will quit testing, probably because Seagate knows from experience the hard drive's problems will only get worse.
You need to replace the hard drive.
You MAY be able to copy personal data you do not want to lose to elsewhere, if you boot the computer from something such as the Ultimate Boot CD than can read all the files on the drive.