WD MyBook on Mac OS, Partition Table Overwritten

How to use TestDisk to recover lost partition
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y10012
Posts: 2
Joined: 05 Mar 2013, 09:51

WD MyBook on Mac OS, Partition Table Overwritten

#1 Post by y10012 »

I have a Western Digital MyBook II External drive on my Mac. The enclosure is configured as a RAID 1, with two 2TB disks (thus is seen as a 2TB drive from Mac).

The drive had two partitions (in addition to the EFI partition). The first contained my media files and was approximately 1.5TB and the second was used for Time Machine backup of certain folders. I only care about recovering my media partition. The partitions were HFS+ Journaled (standard Mac OS).

I accidentally re-initialized the drive with the WD Drive Manager utility, which overwrote the partition table and now the drive shows as a single partition with the default name MyBook and no files visible (i.e., an empty directory). There are more than 10000 media files on the drive (photos, videos, music), and a lot are large files that are almost certainly fragmented, thus I really really need to recover the file system information.

Can someone help me (point me in the right direction) on how to recover the overwritten partition table (with the lost file system)? When I run testdisk on the affected drive, it shows the EFI and MyBook partitions, which is not helpful. When I do a Deep Search, about 20 partitions show up (overlapping). However I am not sure how to find the deleted Media partition, and, more important, how to restore the file system information.

Thank you in advance for any help!

Y.
User avatar
Fiona
Posts: 2835
Joined: 18 Feb 2012, 17:19
Location: Ludwigsburg/Stuttgart - Germany

Re: WD MyBook on Mac OS, Partition Table Overwritten

#2 Post by Fiona »

Did you run Deeper Search?
If your partition would be found and overlap with another one (overlapped partitions are displayed as D for deleted), you can mark that partition and use the left or right arrow key on your keyboard to set it to P for primary.
Using "Write" in TestDisk, you can write your partition to your partition table.
Some information;
http://www.cgsecurity.org/wiki/OS_Notes ... 28Intel.29
If you have an Intel Mac, you should not use pdisk!

Fiona
y10012
Posts: 2
Joined: 05 Mar 2013, 09:51

Re: WD MyBook on Mac OS, Partition Table Overwritten

#3 Post by y10012 »

Thank you for your help. When I ran deeper search, there were many partitions found (about 30), most of which were backups of software installation dmg files. None of these partitions was large enough (about 2TB) to correspond to the lost partition.

I could try a few and see if any directory information appears. However, how do I do that on an Intel Mac if I can't use pdisk? I had tried to do that before, but testdisk would give a write error.
Also, is "Write" in testdisk destructive? Meaning if I select to write a new partition and it doesn't work out, can I go back and redesignate the previous Primary partition?

I have an identical drive to the one that was re-initialized by mistake. I see that the partitions in that drive start on the exact same sectors as the empty partition in the drive that was re-initialized. This makes me think that the old partition information was overwritten. However I am hoping that that the old file system can be recovered, as the new file system is empty. Can testdisk search for catalog files and recreate the directory structure? Or somehow find and reuse the lost directories?

Thanks again,
Yannis
mati73
Posts: 5
Joined: 12 Mar 2013, 15:28

Re: WD MyBook on Mac OS, Partition Table Overwritten

#4 Post by mati73 »

Hello,

I have the similiar problem - I've got a second disk in my MBP with two partitions on it: HFS+ (Lion partition) and NTFS (old Windows partition). I wanted to remove NTFS partition and stretch my HFS+ as much as possible without any touching data on it. I rebooted into Lion recovery partition with Disk Utility on it and instead of removing windows partition and expanding OS X partition, I accidentally changed partition schema to 1 partition schema with the name "Data" making all my data disappear and creating only one empty partition. Is there a help for me?

Quick scan gave me:
1 P EFI System 40 409639 409600 [EFI System Partition]
2 P Mac HFS 409640 976510983 976101344 [Data]
which is current (after my fail) partition table - single, empty "Data" HFS partition. When I did deeper search on Data, it found:
It lasted many hours and stopped (hung) on 53%.

Is there anything I can do? Sorry for attaching my problem in your post, but I think we're pretty much in the same situation. Any help and tips are strongly advised! Thank you in advance for any help!
mati73
Posts: 5
Joined: 12 Mar 2013, 15:28

Re: WD MyBook on Mac OS, Partition Table Overwritten

#5 Post by mati73 »

Hello,

I have the similiar problem - I've got a second disk in my MBP with two partitions on it: HFS+ (Lion partition) and NTFS (old Windows partition). I wanted to remove NTFS partition and stretch my HFS+ as much as possible without any touching data on it. I rebooted into Lion recovery partition with Disk Utility on it and instead of removing windows partition and expanding OS X partition, I accidentally changed partition schema to 1 partition schema with the name "Data" making all my data disappear and creating only one empty partition. Is there a help for me?

Quick scan gave me:
1 P EFI System 40 409639 409600 [EFI System Partition]
2 P Mac HFS 409640 976510983 976101344 [Data]
which is current (after my fail) partition table - single, empty "Data" HFS partition. When I did deeper search on Data, it found:
It lasted many hours and stopped (hung) on 53%.

Is there anything I can do? Sorry for attaching my problem in your post, but I think we're pretty much in the same situation. Any help and tips are strongly advised! Thank you in advance for any help!
mati73
Posts: 5
Joined: 12 Mar 2013, 15:28

Re: WD MyBook on Mac OS, Partition Table Overwritten

#6 Post by mati73 »

Hello,

I have the similiar problem - I've got a second disk in my MBP with two partitions on it: HFS+ (Lion partition) and NTFS (old Windows partition). I wanted to remove NTFS partition and stretch my HFS+ as much as possible without any touching data on it. I rebooted into Lion recovery partition with Disk Utility on it and instead of removing windows partition and expanding OS X partition, I accidentally changed partition schema to 1 partition schema with the name "Data" making all my data disappear and creating only one empty partition. Is there a help for me?

Quick scan gave me:
1 P EFI System 40 409639 409600 [EFI System Partition]
2 P Mac HFS 409640 976510983 976101344 [Data]
which is current (after my fail) partition table - single, empty "Data" HFS partition. When I did deeper search on Data, it found:
It lasted many hours and stopped (hung) on 53%.

Is there anything I can do? Sorry for attaching my problem in your post, but I think we're pretty much in the same situation. Any help and tips are strongly advised! Thank you in advance for any help!
mati73
Posts: 5
Joined: 12 Mar 2013, 15:28

Re: WD MyBook on Mac OS, Partition Table Overwritten

#7 Post by mati73 »

Hello again,

after plenty of hours waiting until deeper search reaches the end, I got the following list:
What should I do to recover first HFS+ partition?
mati73
Posts: 5
Joined: 12 Mar 2013, 15:28

Re: WD MyBook on Mac OS, Partition Table Overwritten

#8 Post by mati73 »

Please, anyone?
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