External HD data vanished

[ArchGabriel]

Hi guys,

I have some serious problem here: I have a 500Gb Samsung external HD and I saved some important back up there. The problem is that some folders content just vanished! I don't know what happened and I tried almost every solution that I found on the internet (foremost, fidentify, testdisk, etc.) but none of them worked.
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Is there anyway to recover my data?
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Please, it is very important!
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Thank you all in advance,

[Bashing-om]

ArchGabriel; Hi !

Have you tried to access your data from the command line ? Have you mounted the data disk manually and see what results ?

Show us what there is to work with, and we can try and mount/access from the command line.

sudo fdisk -lu
sudo parted -l
sudo parted /dev/sda unit s print
sudo parted /dev/sda unit s print

If the hard disk is partitioned "GPT" then "fdisk" can not relate, we do the looking with "gdisk":

sudo gdisk -l /dev/sda
sudo gdisk -l /dev/sdb

If that data disk can not be mounted from the command line then indeed there is a serious problem.

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