My hard drive from my MacBook crashed and died hard last week. I replaced the drive with a new one, and installed 10.6/Snow Leopard on it. The old drive is now in a usb enclosure, and I really need to recover the data from it.

The problem is, it won't mount and when it's connected with USB, OSX doesn't even detect that there's a new drive attached.

What can I do?

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    If the drive is dead you probably need to start looking at data recovery firms. You should also work on setting up a backup system so this can't happen again. – Zoredache Jun 22 '10 at 19:58
  • Is the hard drive even spinning up? – Bobby Jun 23 '10 at 7:49
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    Note that trying to spin up a physically broken drive could destroy it for good, esp. if there's a failure in the mechanical parts (e.g. heads). Note also that spin-up puts the most stress on all the drive's components (both electrically and mechanically). If "really need the data" means "I didn't archive the photos from my holiday", go ahead and try yourself. If you mean "I'm messed up three different ways if I don't recover it", leave it to the pros - chances are, they have more experience with data recovery. – Piskvor Oct 25 '10 at 14:19

Your best bet is to restore from your most recent backup. You have backups, right? :-)

If you don't have backups and the drive isn't even recognized as existing when you plug it in you're probably in Data Recovery Company territory (also see Google: "Data Recovery Services"), and data recovery tends to get hideously expensive.
Out of the 3 linked I would recommend starting with Tekserve -- They deal with Macs regularly, and if they can't recover your data at their facility they may be able to refer you to someone who can.

Realistically unless the data on this disk is of super-critical business importance and was the only copy in the world recovery probably isn't worth the price. If it IS super-critical this is an expensive lesson in why you need to start backing up (If you're using a Mac I suggest using Time Machine: Mostly automatic & a good fit for 99% of users)

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    Regarding TekServe, I've used them twice, for a friend and for my then g/f now fiancée. They are cheap because they don't actually take apart the hard drive. They just hook it up to a machine thats basically a harware version of ddrescue. The great thing about their service is if they don't recover enough data, you can chose not to pay them and not get any data back. – Justin Dearing Jun 22 '10 at 20:25

If the harddrive is still recognized as a harddrive on the hardware level, you can use ddrescue: http://www.gnu.org/software/ddrescue/ddrescue.html .

I had great success recovering data from a partition that Windows would no longer mount.

ddrescue basically creates an image of a partition, same as any imagin tool. The critical difference is that it will not hang or inifinitely retry on read errors; rather it will skip damaged regions, but remember them and revisit them after copying everything that had no errors. That way, you quickly get the undamaged parts, and then can keep it running until it no longer recovers anything.

Afterwards, you can run fdisk on the image to recover what's there.


Put a pricetag on your data.

If that number comes out four-digit, head to a professional Data Rescue Service near your location.

If the number comes out three-digit, find a local computer service who may try something out.

If it is two-digit, wave your data goodbye.

There are several ways in which a disk can die. Depending on what the failure consists of, your chances vary quite a bit.

Set up a proper backup, too.

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    (\These digits are US dollars) – endolith Oct 3 '11 at 21:30

You can try SpinRite from Steve Gibson. It seems to be good at recovering data from failed HDs.


SpinRite sounds like a great solution until you find you have to have a PC to run it on your Mac disk. Additionally, it sounds like it works similarly to Gnu ddrescue (though with some additional logic that fills in missing data where it can). Tech Support for SpinRite said they didn't have any cases of their program running on Mac hardware which amazed me because I can boot a FreeDOS CD on my Mac (that's what they use but they said they require BIOS too). They did have some reports from users that it works in VMWare by booting an image of their CD.


If you have a windows computer there is a bunch of freeware recover tools you can find at http://www.portablefreeware.com/index.php?p=2&q=recover which includes Recuva .

Also, you might try a bootable Linux rescue kit.


My friend is Disk Warrior. It helped me some times when a Mac didn't want to start up because it didn't find any hard disk to start from.

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