I am helping a friend to recover data from damage external hard drive .

(USB 2, 120GB, WD, single partition, FAT32)


When plug in this HDD into a windows PC, the HDD can be detected, but the drive did not show up. Checked using 'Disk Management', Found 'Disk 1' and shows that Disk 1 is not initialized.

1st Attempt:

Tried the 'Freezer trick' twice.

First time: manage to view the drive for 5 seconds, tried to copy all files, it stuck there after press Ctrl+C.

Second time: No luck, back to Not Initialized condition.

2nd Attempt:

After browsing through few article, I decided to try Ubuntu for the first time.

I am running Ubuntu on a DVD disk. After boot up the system, the external drive is not mounted. Through some trial and error using Terminal, I manage to find out that:

/dev/sda is my laptop HDD (750GB, with multiple drive)

/dev/sdb is the external HDD (120GB, Damaged drive)

At first, I try to use Testdisk 6.14 to recover data, but due to the external HDD is not mounted, Testdisk unable to detect it.

So I tried to mount it using Command in Terminal:

sudo mount /dev/sdb /media/ubuntu -t ext2


mount: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so

Then I tried

dmesg | tail

Message (*) shows

[33935.683953] sd 6:0:0:0: [sdb]  
[33935.683954] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[33935.683955] sd 6:0:0:0: [sdb]  
[33935.683956] Sense Key : Medium Error [current] 
[33935.683958] sd 6:0:0:0: [sdb]  
[33935.683959] Add. Sense: Unrecovered read error
[33935.683960] sd 6:0:0:0: [sdb] CDB: 
[33935.683961] Read(10): 28 00 00 00 00 02 00 00 02 00
[33935.683965] end_request: critical medium error, dev sdb, sector 2
[33935.683991] EXT4-fs (sdb): unable to read superblock


  1. What is the meaning of Message (*)?

  2. Is the data in this HDD still recoverable?

  3. What should I do next?


The sense key "medium error" is feedback from the SMART system on the drive.

You can try smartctl -a /dev/yourdrive to get more information, but to me it already looks like the drive is fried. Replace it and restore data from backup.

If you don't have a backup a data recovery expert can help you, they do tricks like changing the HDD medium into other hardware, which you should not try to do at home.

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In the second attempt you're trying to mount the drive as an ext2 filesystem...to mount as fat use the -t vfat option.

You can also try to image the drive with dd like dd if=/dev/hdx of=/path/to/image and then mount the image.

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