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The DOS Zone - FAQs


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How can bad sectors be fixed?


Please view my Notices page before viewing this area, it is not complete!
This is work in progress.


Bad sectors are due to physical defects on the surface of the disk and therefore cannot be fixed.

If you have clusters marked as bad then it may be worth running an anti virus program since some viruses will mark a cluster as bad, then use it for some purpose. You could also try formatting using "format /u", if you are using MS-DOS 6.2X use "format /u /c" instead. But as I said before if it really is a bad sector it cannot be fixed.

If you have an old drive you may be able to hide the bad sector(s), by doing a low level format. Instructions on doing that can be found in the Disk And File System Issues section of this FAQ.

Newer drives have a in-built bad sector swapping ability, whereby a bad sector is swapped for a good one from a certain number of reserved sectors. Because of this chances are that if bad sectors are appearing then there are a lot more than you are being made aware of.
Depending on where the bad sector is on the disk, the file system may be able to work around it, but it's not advisable to use a disk like this for important data.


Trawled this site and still can't find the solution to your problem?
If so I highly recommend The DOS Board.
It has several good techies waiting to answer your questions and I hang around there a lot too.

Copyright © Jonathan Fox 2000-2002.