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So me and my friend were installing Arch Linux on my external hard drive. My external hard drive had no data on it, ready to roll. My friend had partitioned my external hard drive (I am positive that there was no error in this part of the process), but after he had exited out of cfdisk, he had accidentally typed

mkfs.ext4 /dev/sda2 (my internal hard drive) instead of

mkfs.ext4 /dev/sdc2 (the drive he was supposed to format).

I asked, "Hey, isn't my external hard drive sdc, not sda?"

Then he starts freaking out, and he shut down the Arch LiveCD and tried to reboot into Windows (on my internal hard drive). Lo and behold, this came up:

Windows failed to start. A recent hardware or software chance miht be the cause. To fix the problem:

  1. Insert your windows installation disc and restart your computer.
  2. Choose your language settings and click "Next."
  3. Click "repair your computer."

Status: 0xc000000f

Info: The boot selection failed because a required device is inaccessible.

I immediately held the power button until it turned off, and haven't turned it on since, in fear of doing something worse to my computer.

So, for my questions:

  1. Is my C: partition wiped, lr is it just my boot partition? I suspect it was the C: drive....
  2. I want to create a full binary backup of my (former) C: drive before I perform any rescue attempt, so I can do more than 1 attempt to recover my data. Is this even possible, and can I actually use this to actually do multiple rescue attempts?
  3. There are 2 major things I want to recover. One of these is my Compositions folder, which is in the C:/Users/MyName/Libraries/Documents/Compositions folder. These files have a weird extension (.mscz), which I doubt certain file extension-sensitive data recovery tools can find. Can some tools find files with unknown extensions?
  4. Do files in lower directories have a higher chance of being saved? Because my most important stuff is held in C:/Stuff.
  5. I would prefer that the software recovery tool would be free.
  6. I had deleted the HP RECOVERY partition a while ago, stupid me. However, I have quite a few Win 7 System Restores that were fairly recent. Are these on the C: drive? if not, can I use these to reinstall Win 7 after my data is (hopefully) recovered?
  7. I have a set of HP recovery disks, if those are of any help.


My computer is an HP laptop with Windows 7 x64 (single boot) a 750GB hard drive (~200 GB unused, 6% fragmented last time I checked. I only need to recover around 2GB of data; the rest I can easily replace). My friend has a fully funcioning computer, and I have an external hard drive (1TB) that I can use in the recovery procedure. We both have a couple of USB's that we can use as LiveUSB's.

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up vote 2 down vote accepted
  1. Windows doesn't use a separate boot partition, so it probably is C:. It isn't exactly wiped, though - it's just that the filesystem metadata has been overwritten. Most of the contents of the files are probably still there, but inaccessible.

  2. Yes, it's possible and it's a good idea. If it's a 750 GB drive, though, keep in mind that the image will be 750 GB. You'll need a lot of space to do this. Run dd if=/dev/sda of=<output_filename> bs=16M (the block size doesn't matter that much, except that it should be a multiple of the disk sector size - I've seen it suggested that it should be set equal to the size of your drive's cache). This will produce a binary copy of exactly what's on the drive. You can, with a bit of fiddling, generate a VMware or VirtualBox image from that, which you can run recovery tools on.

  3. The extension matters not at all. Some file-recovery programs work on certain file types by detecting the structure of the file itself (or maybe just magic numbers in the headers) - obviously if the program isn't written to recognize a certain file type, it won't work regardless of the extension.

  4. This is unlikely to make any difference.

  5. Try TestDisk.

  6. The System Restore points may or may not be intact, but you won't be able to recover a full OS installation from those. You'll probably have to find actual installation media.

  7. These might allow you to to restore the OS, or they might not (recent recovery disks tend to only be helpful in recovering drivers and whatever bloatware the manufacturer installed). In any event, don't try to use them until you've recovered all the data you can.

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Should I take my external hard drive and put Ubuntu or something on it, and then copy the binary? – user2533402 Jan 14 '14 at 20:47
You don't need to install it - dd is a basic system tool, so any LiveCD should work. – user55325 Jan 14 '14 at 22:57
Just found out that I left this question open. Thanks for all your help! :) – user2533402 Jun 23 '14 at 14:42

Best free apps for this:

  1. Easeus partition master
  2. Minitools partition wizard

I have used both many times. Connect your hard disk in another system and try to recover lost partition.

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