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I have a 500 GB hard drive with one NTFS-partition on it. I can mount it with Ubuntu and view the contents. But when I try to copy something, I get an I/O error.

Ok, I tried to make its image with dd. I/O error as soon as it starts.

I have installed ddrescue, but its manual page says not to use it with drives, failing on I/O.

Can I manage to get some information from this drive and how to do this?

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termal shocks do sometimes work. I've had a hard disk crash hard on me and really needed some of the data on it (long story short, my other hard disk died in another machine a few days before). The disk wouldn't boot. Two hours in the fridge, dry it with paper if needed when it comes out, try. Rinse and repeat. After the third try or so the disk booted. Once. I had the time to 'dd' over the network it using a Linux bootdisk. That hard disk never ever worked again. I'd say out of 5 hard disk I tried this on it worked twice. –  YellowSquirrel May 20 '10 at 10:10
    
and depending on the hard disk's temperature, it's "audio fingerprint" (the noise it makes when starting up/trying to start up) will vary. This is a desperate thing to try. Kids don't try this at home etc. –  YellowSquirrel May 20 '10 at 10:12
    
I will try this method right now :) –  exquisitor May 24 '10 at 7:35
    
It didn't help :( –  exquisitor May 24 '10 at 11:34

2 Answers 2

up vote 0 down vote accepted

SpinRite is the right tool to detect and correct this kind of low-level read error.

I have saved many hard disks this way. Although in one case a hard disk was beyond repair and a data recovery service company also gave up.

I use SpinRite 6.0 and it costs USD$89. Note that in some cases SpinRite hangs if there are USB hardisks connnected to the computer. The work-around is to remove the power from USB hardisks. If the trouble is with a USB hardisk then a work-around is to take the hard disk out of the enclosure and put it into the computer, connected as a normal SATA harddisk.

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Can it do more than 'gddrescue'? I think that it has a similar algorithm of guessing right byte. And if 'gddrescue' couldn't cope with this disk, I am afraid that SpinRight won't help too. –  exquisitor May 24 '10 at 7:33
    
@Lexsys: I don't know about gddrescue (I found packages.debian.org/sid/gddrescue) - do you have a reference to a good description? SpinRite tries to influence the physical movement of the read heads over the damanged sectors in order to get the right read signal that will allow correct reading of the sector. It is in-place recovery - data is written back to the disk in case the reading of the bad sector succeeds. It may try up several thousand times on the same sector. –  Peter Mortensen May 24 '10 at 10:16
    
@Lexsys: there is a very detailed description of how SpinRite works in this document: grc.com/files/technote.pdf, "SpinRite. What's Under The Hood." –  Peter Mortensen May 24 '10 at 10:32
    
@Lexsys: I found a more accurate reference, grc.com/srrecovery.htm: "During the defective sector re-reading, the drive's read/write head is deliberately relocated to either side of the troubled sector -- and at varying distances -- so that when the head is again placed over the troublesome sector, it might come to rest at a slightly different position than it did last time ... and might allow the sector to be perfectly read." –  Peter Mortensen May 24 '10 at 11:31
    
@Lexsys: Partial recovery of a sector is supported (instead of discarding the entire sector). From grc.com/srrecovery.htm: " ... with this "mostly correct" now-readable sector so that all but a few data bits of the file can still be read and used. This is obviously a huge improvement over losing the entire file due to one of its sectors being completely unreadable. –  Peter Mortensen May 24 '10 at 11:33

The whole point of ddrescue is that it is designed to be run on drives that you can't gain access to in any other way. You'll want to run it as few times as possible, in order to get an image of the disk. Then you can run tools against that image to try and recover files - I quite like Foremost.

See also this Ubuntu wiki page for some really good information on recovering data.

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Thank you for the useful link. But 'ddrescue' can't read the disk in my case. –  exquisitor May 24 '10 at 7:34

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