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johhnie_777

Member

Registered: 2026-04-05

Posts: 3

[SOLVED by mighty seth] Help me to recover data from USB please

When I try to mount my usb stick with dolphin it says:
An error occurred while accessing 'X.X GiB Removable Media', the system responded: The requested operation has failed: Error mounting /dev/sdc at /run/media/user/very-very-very-long-number: cannot mount /dev/sdc read-only
(the X.X and the very-very-very-long-number redacted by me)
Last time I was using that USB I had to unplug it unsafely unfortunately. That's prob the issue.
USB's fs is ext4.
Please help, I really need to recover that data.

Edit: forgot to mention that I tried to edit the /sys/block/sdc/ro from 1 to 0 as root with nano, but it didn't work: [ Error writing /sys/block/sdc/ro: Permission denied ]

Last edited by johhnie_777 (2026-04-05 08:33:27)

seth

Member

From: Don't DM me only for attention

Registered: 2012-09-03

Posts: 74,253

Re: [SOLVED by mighty seth] Help me to recover data from USB please

cannot mount /dev/sdc

Is the stick formatted as unpartitioned "superdisk"?
Are there IO errors in the journal/dmesg after attempting to mount it?

sudo mkdir -p /mnt/sdc
sudo file -s /dev/sdc
sudo mount /dev/sdc /mnt/sdc

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johhnie_777

Member

Registered: 2026-04-05

Posts: 3

Re: [SOLVED by mighty seth] Help me to recover data from USB please

While I was waiting for the answers I did this:

sudo fsck.ext4 -n /dev/sdc
[sudo] password for user: 
e2fsck 1.47.4 (6-Mar-2025)
Warning: skipping journal recovery because doing a read-only filesystem check.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Feature orphan_present is set but orphan file is clean.
Clear? no

/dev/sdc: 6248/488640 files (0.1% non-contiguous), 228030/1954176 blocks

Is the stick formatted as unpartitioned "superdisk"?

I really don't know, I don't remember.

Are there IO errors in the journal/dmesg after attempting to mount it?

on journal:

Apr 05 xx:xx:xx johhny-pc kernel: EXT4-fs (sdc): write access unavailable, cannot proceed (try mounting with noload)

sudo dmesg | tail -n 50

EXT4-fs (sdc): write access unavailable, cannot proceed (try mounting with noload)

Edit: the dmesg has also this:

 [sdc] Write Protect is on
 [sdc] Mode Sense: 43 00 80 00
 [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
 [sdc] Attached SCSI removable disk

Last edited by johhnie_777 (2026-04-05 08:11:37)

seth

Member

From: Don't DM me only for attention

Registered: 2012-09-03

Posts: 74,253

Re: [SOLVED by mighty seth] Help me to recover data from USB please

try mounting with noload

sudo mount -o noload /dev/sdc /mnt/sdc

Does the usb key have a write protection feature?
Otherwise the controller might have entered read-only mode (and fused) to protect data integrity on degraded NAND cells.
(You should then be able to read the data but the key is toast)

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johhnie_777

Member

Registered: 2026-04-05

Posts: 3

Re: [SOLVED by mighty seth] Help me to recover data from USB please

Does the usb key have a write protection feature?

No.

Otherwise the controller might have entered read-only mode (and fused) to protect data integrity on degraded NAND cells.

I don't care about the stick, the data was my only concern. Thank you for explaining.

(You should then be able to read the data but the key is toast)

Yes, I was able to recover the data fully. I'm so thankful. Highly appreciate your help.