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I have a lap top that a friend of mine would like me to fix. It is giving a blue screen on boot up. When I looked up the error message it indicates that I should run a check disk.

Is this dangerous? Should I try to off load stuff from the hard drive first?

I ask because I had a hard drive of my own that when I ran check disk it wiped a bunch of "bad sectors" and I lost most of the info on it (but it had been going bad).


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Backup vital information, just to be sure. – Mercer Traieste Jul 16 '09 at 7:27
up vote 5 down vote accepted

Under normal circumstances, it's perfectly safe as long as you're using the one designed for your version of Windows.

However, it is possible that there are important files on the bad clusters, which haven't been marked as bad, and those clusters may be working intermittently. By "fixing" them, the drive ignores those clusters, and therefore those files are inaccessible.

But then you go and try to recover the bad clusters and you can get some of it back sometimes. Used to be you'd end up with files like "?utoexec.bat" and such; not sure how it works recently.

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Yes I would try and get your data off the drive before running a chkdsk. You could also try something like SpinRite if your data is important to you.

Another option would be making an image of the drive using Ghost, LiveState Recovery, or StorageCraft ShadowProtect.

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As with all disk utilities, there is a chance it can go bad so you should always backup your important data before you do such things.

That said, in my experience, chkdsk has never killed my hard drive or caused me to lose data, but everyone has their own different experiences.

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I've lost data on several occasions after running a chkdsk /F, granted it was already corrupt but I may have been able to get some of it back had I backed up first. – glenneroo Oct 13 '11 at 17:05

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