Corrupted 500 GB external HDD

How to use TestDisk to recover lost partition
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Posts: 2
Joined: 25 Nov 2012, 10:12

Corrupted 500 GB external HDD

#1 Post by fengsuhi »

Hi, I accidentally ejected a 500 GB WD external HDD while it was still operating under Mac OS X Snow Leopard. The disk was formatted to a 70 GB HFS and 430 GB NTFS.

Now the NTFS partition cannot be mounted neither under OSX nor Windows. Disk Utility shows the correct size but Windows thinks it is RAW and ask for formatting.

Testdisk (under Win) showed two identical NTFS partition, I ran a quick search which took about 60 hours (with the auto selected EFI GPT setting). Testdisk tells me the partitions can't be recovered:
testdisk_screenshot.JPG (100.53 KiB) Viewed 1925 times
After pressing continue:
testdisk_screenshot_02.JPG (81.72 KiB) Viewed 1925 times
In my testdisk.log there are a lot of "lseek err Invalid argument".
Uploaded to Pastebin:

Any suggestions?
Thank you.
Posts: 2
Joined: 25 Nov 2012, 10:12

Re: Corrupted 500 GB external HDD

#2 Post by fengsuhi »

I did a risky move: overwrite the bad boot sector with the backup boot sector. Now everything is fine. Thanks for developing Testdisk.