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After cloning a Windows hard disk using dd, Windows failed to startup, giving 'disk read error'. Although I know that there are faulty sectors on the old disk, the startup completes, albeit slowly. Whilst I wouldn't have been surprised if the new disk exhibited the same problems as the old, I'm surprised that it won't even start up. Is this a different problem that is correctable? (I had to edit the BIOS after doing the copy to start up from HDD rather than CD although I'd removed the CD. Could this be something else in BIOS that needs correcting?)

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dd isn't made to deal with faulty hardware. Try ddrescue instead. You can install it by running

sudo apt-get install gddrescue

I suggest reading's extensive manual about ddrescue before running it.

Following the comment from psusi: This is probably not an issue with dd. You could check your old disk's SMART values with the Disk Utility and look for the Reallocation Count and Reallocated Sector Count properties. If they aren't zero, chances are good that the old disk lost some information important to Windows before cloning the disk.

Another possibility is a bad new drive (single bad sectors in new drives aren't necessarily a problem - I ran my 1TB WD Black drive for 15.000 hours and it came with two bad sectors, which got mapped out during an offline test with WD's diagnostic tool). Again, check with the Disk Utility to make sure.

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dd normally errors out at the first bad sector. You can make it continue after read errors with the conv=noerror option, which is pretty much what gddrescue does. – psusi Jan 6 '12 at 14:39
Hm, true that. Maybe the bad sector got mapped out and dd just copied a good one without the data needed by Winodws (I once got the same Windows error msg when the disk had two reallocated sectors). – htorque Jan 6 '12 at 14:51

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