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01-10-2001, 09:42 PM
Is it possible to repair bad sectors on a hard drive? If so, how do you go about it?

01-10-2001, 10:13 PM
The 'Norton Disk Doctor' should do this for you.

01-10-2001, 11:09 PM
Bad sectors are usually a sign of bad things to come. Its usually the case of an old drive or one that has suffered damage.
Bad sectors have a habit of breeding on your hard disk. Its a good indication to get a new drive quickly or face the consequences of loosing data at random. Its possible with some software to recover data or bits of from bad sectors. But Ive never seen a programme that can repair them sucessfully or for any lenght of time as they are generally created by physical damage or age. Programmes like Nortons Disk Doctor will mark them so they cant be used again..But as I said they tend to pop up elsewhere on your disk at a later date.

Good Luck

==Orac==

02-10-2001, 07:20 AM
Quite often bad sectors aren't bad phisically at all. Scandisk will set them aside as unusable for whatever reason, but when you run partition magic or norton utilities at a later date, they will give you the choice to reinstate the bad sectors, then they are gone forever. This has happened to me on several computers.

03-10-2001, 05:34 PM
Bad sectors reported as bad by Scandisk or NDD are bad sectors. Whether they are detected as bad depends on the temperature, humidity, the phase of the moon, or whether it's Tuesday.
When the operating system reads a disk, it checks each block or sector for errors. If it finds an error, it will try again. You will hear this happening when reading a flakey floppy disk. It will retry several times before giving up and giving you the famous Abort, Retry, Fail choice.
A testing programme should be much tougher. I suspect that in the factory test of IDE disks, a fail on the first read of a sector will cause the sector to be mapped onto one of the spare sectors in the track, and more than a small number of bad sectors in a track will cause the whole track to be mapped out. That is why new IDE disks have no errors. Old MFM disks came with a list of bad sectors, and you had to enter them by hand if your formatting programme was not equally tough.
Scandisk obviously ( know by listening when checking floppies) allows some retries before marking bad blocks.
A 'softhearted' scanning programme which allows marginal sectors to be used will inevitably lead to tears before bedtime.
A history of new bad blocks turning up means that the user's data are living on borrowed time. Disks are very cheap these days.