Recovering Mac partitions on a WD MyBook external drive

How to use TestDisk to recover lost partition
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Posts: 1
Joined: 28 Aug 2014, 02:05

Recovering Mac partitions on a WD MyBook external drive

#1 Post by deerefanatic »

Hello all, new here, not new to computers or IT in general. Here's what I'm dealing with.

Friend of mine has a 1TB WD MyBook external hard drive. Has firewire and USB 2 ports. She had it partitioned since she got it in two partitions, 1 bootable clone of her Mac, the other as a data partition where she kept all her pictures. She recently upgraded her Mac OS the the latest version (I'm not a Mac guy, mostly windows and learning Linux). Afterward, she decided it would be a good idea to make a new bootable clone of her updated system partition. The problem being, the program she used wiped out BOTH partitions, partitioned it as 1 giant clone partition and wrote the data! And she didn't realize the problem until it was over.

Now, she says that it was partitioned more or less in half, (say 500 GB each). My guess is the data in her backup partition is probably still there since the bootable partition was undoubtedly at the beginning of the drive, and shouldn't have actually overwrote the data.. (One can hope, right?)

I initially was going to use photorec to recover the pics/mp3's, etc. After 44 hrs, it had only searched through 1/6 of the drive's capacity. So, decided to do a scan with testdisk and see what I could accomplish there. Quick search only showed the partitions that are currently on the drive. I started a deep search. Currently I am at cylinder 2626/121514 after nearly 2hrs! Is it normal for testdisk to be this slow? I don't suspect any mechanical problems with the drive. Photorec started out going through sectors fairly quickly at first.... As of last night, (after 24hrs) it was at sector 300,000,000,000 ish. Tonight when I got home, it hadn't made it to 400,000,000 and thats a drive with 1,900,000, 000 sectors! Not sure why it slowed down so drastically. :(

I am using the firewire connection, not USB 2. Running on windows XP.

Any thoughts or help is appreciated.

Posts: 2
Joined: 16 Sep 2014, 09:23

Re: Recovering Mac partitions on a WD MyBook external drive

#2 Post by unimatrix725 »

I know it has been a long time and I am no GURU regarding recovery. I would suspect since it wrote after partitioning it is a lost cause. I would let the recovery app run until it is done, if anything was really important. You may be able to recover some things. More likely to recover in the space that was not written to. I learned back in the day, if you accidentally format/partition/Virii, etc then Do Not Write AnyThing to said drive! I am up for corrections. I am here looking for help about my mac also. Slightly different and will post accordingly. I hope you have luck with this.