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Yesterday I found a corrupted file in my external usb drive. Since I am using the drive quite often (I am running my vms over there) I decided to run the chkdsk on it

This is the result

488384000 KB of total space on disk.
351202364 KB in 1042390 file.
489920 KB in 81101 indexes.
    16 KB in damaged sectors.
1204584 KB in use.
65536 KB used from the registry.
135487116 KB available on disk.

therefore it has found 16KB of damaged sectors. Now the file is recovered

Should I be worried about the HD and run chkdsk periodically from now on?

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up vote -1 down vote accepted

I would run chkdsk periodically to make sure that this doesn't degrade further, but a few damaged sectors here and there is normal and nothing to be particularly worried about. During normal operation, a hard disk will (transparently to the operating system) re-map any damaged areas to non-damaged areas, and report that in the SMART data.

Which brings me to the next point, that you may want to download and install (if you don't have already) a utility which will allow you to inspect the SMART data from the drive. I'm not too sure what's available in Windows to do so or if it'll work over a USB connection, but that will tell you if the drive is remapping large amounts of space or only a few odd blocks here and there. If it is remapping a lot of space, then you should consider replacing the drive as soon as reasonably possible to avoid the risk of data loss.

The drive can transparently remap only a given amount of data, and when it runs out, then data errors are going to start trickling through to the OS. Which is why you want to keep an eye on any damaged blocks count reported by the OS utilities. If that number increases by any significant degree, that is a good indication that the drive is about to fail.

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if the hd moves damaged areas transparently, will chkdsk detect that the space is running out? or should I download a tool which is specific for this task? I can also run the check from a linux machine, if there is any tool that helps – mottalrd Oct 17 '12 at 9:10
Every hard disk manufacturer has their own testing software that you can burn to bootable CD. Run the full test with that. Short test takes 5 min, full one takes 3 hours. – cloneman Oct 17 '12 at 10:32
I'm pretty sure chkdsk doesn't read SMART data, so it won't know anything about in-hardware remapping. All it cares about is that when it asks for a specific disk block, the drive returns something that it can analyze. As for diagnostic/testing software from the manufacturer, it may or may not work with the drive connected over USB, but it is certainly worth an attempt. – Michael Kjörling Oct 17 '12 at 11:16

If you find damaged sectors at all, it means the drive has already gone through its remap pool and has run out of blocks to transparently remap. That means your drive is dying. You should replace it now.

You should never see bad sectors from a normal OS utility, because the drive should be hiding them in the background.

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If a sector is too damaged to remap it will be reported. It only auto remaps when it is above a error threshold but below what the ECC can handle. If it is above that level it reports back to whatever queried the sector. – Scott Chamberlain Oct 21 '12 at 18:16

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