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So I'm an idiot

And last night, half-asleep, in an attempt to mount a .img to my exFAT-formatted external drive so I could boot Ubuntu from it, I ran dd if=foo.img of=/dev/disk1 like the Ubuntu guide here says to, except I forgot the bs=1m argument. I realized I had messed it up, and Ctrl+C'd the running program, but not before it had written a couple mb of data to the disk. It now refuses to mount on both OS X and Windows.

My question: is there any way to recover an external drive that has been corrupted in such a fashion?

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You may want to try using GParted to "reformat" the drive (as exFAT,) then reboot to Windows and use a file recovery tool on the drive. (I think Recuva might be good for that - not sure if it supports exFAT, though...) Also, don't feel too bad. I accidentally reformatted my WHOLE internal hard drive, in a manner MUCH worse than what you did. Formatting the wrong drive happens to the best of us (namely ME ;P) so don't beat yourself up over it. :) – JamesTheAwesomeDude Apr 7 '13 at 5:19
@JamesTheAwesomeDude: Why of all things would you recommend something even more destructive before running data recovery? Recuva and similar apps aren't magic bullets that guarantee recovery. – Karan Apr 7 '13 at 14:14
@glittershark: Try TestDisk, it might help. – Karan Apr 7 '13 at 14:15
@Karan The supposedly "destructive" process of reformatting the drive only dorks with a wee bit of data in the very front of the disk (provided he's using GParted like I told him to,) - data that is A) Most likely already not important data - it was already being used to mark the drive as exFAT beforehand and B) Already completely lost - he already overwrote a few megs of data. On top of that, recuva can only scan drives that have a letter. For Windows to assign them a lettter, they have to be mounted, and therefore not corrupted. – JamesTheAwesomeDude Apr 8 '13 at 4:46
glittershark, are there any important files on your drive that you need to recover, or do you just need to get it working? – JamesTheAwesomeDude Apr 8 '13 at 4:48

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