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I corrupted my data by taking out the SD card (which was used as internal storage) multiple times without running:

Eject/Unmount

Since using the SD card as internal storage was encrypted the card to be used only inside the same device (Nokia 6.1+) and the card's data wasn't accessible neither in another device nor inside an SD card reader.


So, I reinserted this 1st SD card back in the device on which it was used as internal storage.

Then, in order to back up the data (which was not readable even in same device).

Copied the data (around 30GB mainly media files) from adopted shared internal storage to my PC via MTP using a USB cable.

Data was not readable in the PC as well.

Now, I don't know whether the data that I copied to and is present in PC is simply just corrupt or corrupt and encrypted.

I don't have the 1st SD card anymore.

All I have is the corrupt/damaged data stored on my PC.


Can anyone help me out here first to know whether the copied data on my PC is simply just corrupt or it's encrypted as well along with being corrupt?

Tried various recovery and repair methods for months but couldn't repair the corrupt data.

Back to the present: Today, I tried to repair the corrupt data (Mainly images) using online tools but couldn't.

The online tools required some normal images from the same device as reference files.

So, again used a new SD card as internal storage just so I could use the normal images from the internal shared storage as reference images.

After successful using this new card now even these new (unimportant) images are not opening in the same device.

Thumbnails of around 30% of images are visible in the Google Photos but not all images are opening out of these 30% and the rest are neither showing thumbnails nor opening.

On opening from the file manager (default as well as 3rd party) not even image thumbnails are visible for any of the images.

On opening individual images on the file manager, it displays the error: “Could not open file.”


How can I repair the data (images and videos) presently inside my PC which got corrupted after 1st use of 1st SD card as internal storage?

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    The files are gone. Sorry. But the thing you need to understand is if the SD card is encrypted and you can read it, it means that the SD card was encrypted and when you mounted it, all of the files were readable… Corrupt but readable. So what you copied is decrypted and damaged data. And there is no way to recover these files. Please invest in better quality SD cards and even a backup process. Feb 4, 2023 at 16:48
  • How many times are you going to ask this same question… under different user names now...
    – Tetsujin
    Feb 4, 2023 at 16:59
  • @Giacomo1968 the latest adoption of new SD card was successfully done and I didn't "Eject" the card but even then only around 30% images and their thumbnails are visible, that too, only from the Google Photos only. None are readable in the file manager inside the same device.
    – Abhishek
    Feb 5, 2023 at 4:37

1 Answer 1

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Feel free to share some of you corrupt files, link to them in OP. I'll examine them and then add analysis to this answer so it's useful in general.

Whether a JPEG photo can be repaired depends on one thing entirely: Does the file contain JPEG data. Note that encrypted data, even if the data that was encrypted is JPEG is not in itself JPEG data.

NO JPEG DATA = CANNOT BE REPAIRED

I repair JPEGs often so I made a tool for it, here. I am not saying you must buy this tool, but the demo may already be of some help. The tool which you can find here allows you to open a corrupt file and examine the 'entropy'. Commonly JPEGs that can not be repaired will contain either low or super-high entropy.

'JPEG-like' entropy, the tool will display entropy value in green:

enter image description here

Non JPEG-like entropy, the file is filled with zeros, the entropy value is in red characters:

enter image description here

To examine files in bulk use the extract option, the error log will display entropy for each of the files:

enter image description here

Note that:

  • entropy is a guide-line only!
  • in case of encrypted data rather than 0.00 you'll see 8.00

In addition you can examine the files using a hex editor like HxD.

  • Open file
  • Search
  • Find > HEX TAB > FF > Search all

enter image description here

If you find FF nn throughout the file and nn =/= 00 then you are not looking at JPEG data. In example screenshot we're clearly not dealing with JPEG data.

NO JPEG DATA = CANNOT BE REPAIRED

If the files were encrypted, based on encryption (FBE) you can sometimes spot the string 'CONSOLE'.

enter image description here

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  • Can you make a room or chat so that I can share data & details directly with you?
    – Abhishek
    Feb 5, 2023 at 4:24
  • I have no idea how to do that. Feb 5, 2023 at 13:00
  • Let us continue this discussion in chat.
    – alecxs
    Feb 5, 2023 at 17:27
  • @alecxs can you please restart the previous chat/room again?
    – Abhishek
    Feb 21, 2023 at 5:28
  • I have asked moderator to re-open the chatroom
    – alecxs
    Feb 21, 2023 at 8:12

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