SD problem for hardcore problem solving users

[robodoid]

i have a CUBOT Magic. I try to fix my SD card the last 12 days. I encrypted the phone but i don't remember if that was before or after i put the SD card I have set SD card as the default write disk


There is not a 'decrypt sd card' feature at the phone too My Android is 7.0


I tried almost everything from software, minitool, easeus, diskinternals, diskgenius.... Even i see the partition of the SD card i can't restore it (Android 6.0 ARMMeta Partition and Android 6.0 ARM EXT Partition)

The problem started when the phone literally rebooted on itsown when i played a Clash Royale using (NOX-app++ many accounts tool _guide) It rebooted with a message to reinsert the SD card and here is where the problem started I search for malware with 4 different programs and i don't think it's ransomware or something related with a virus

You people are my only solution because i have some photos in there i don't want to lose....

Thanks everyone for his time

I attach related photos of the problem (from the storage, sd card contents, security.)

 

[B. Diddy]

Welcome to Android Central! Sorry, can you clarify what the problem with the card is? Is it not being read at all? Was it formatted as Internal Storage or Portable Storage?

 

[robodoid]

Hi Diddy,
SD looks OK when it boots but even i have some stats like the space it uses i have no files present
SD is the default write disk as i set it
Image 1 shows that SD is reported OK
Image 2 the 0 files i see when i tap on this storage option
Image 3 that there is no decrypt sd card feature
I can't chkdsk the SD, chkdsk reports as RAW
All of these happened with a sudden reboot...

 

[B. Diddy]

I'm not quite sure what you mean by the SD being the default write disk. Is it formatted as Internal Storage or Portable Storage? (Not all phones give you this option -- if you didn't have this option, then it's Portable Storage). Are you referring to an option in the system settings that make the SD the default storage location for app data?

 

[robodoid]

Hi Diddy,
thanks for your update.
Check the first image where it asks you if the SD will be the default write disk and the radio button that is checked
I assume everything you store from that point on will be stored to sd and used as internal storage but this is my perception
The problem is that the SD shows 0 files making me think that either the partition or the file system is corrupted in a way
The issue is that i don't know how to correct it (if this is the reason of the problem of course)

Regarding the Internal Storage or Portable i was not asked

 

[B. Diddy]

Oh, now I see. I believe that just means the SD card is set as the default storage location for downloaded files and app data (but not app installation). When you try to format an SD card on the phone, if it doesn't give you a choice between Internal Storage and Portable Storage, then the phone doesn't support Adoptable Storage (i.e., the ability to format the card to become part of the phone's Internal Storage), and therefore the card acts as Portable Storage. Can you try formatting a blank card and see if it prompts you to choose between Internal or Portable?

Chances are that the card has become corrupt, and can no longer be read. If you remove the card from the phone and insert it into your computer, can the computer read anything?

Another possibility (if the phone actually does support Adoptable Storage and the card was formatted as Internal) is that the phone somehow lost the encryption key for the card, which again means the card can no longer be read. Formatting a card as Internal encrypts the card to the phone -- and only that instance of the phone, meaning that if the phone is factory reset for some reason, then the encryption key is lost.

You mentioned using NOX-app++ -- this could also be the cause of your problems, since it doesn't appear to be sanctioned by the Google Play Store, so there's no telling what kinds of problems it could cause on your phone.

 

[robodoid]

I fired Ubuntu with fsck to see if there is a something that can be fixed but looks like as you said before the internal format of the SD (i double checked it and saw at the phone that give you the option to format it as portable so the internal format is already used) had a custom format type outside of the ordinary

SO i assume the SD is format as internal with a custom format due to encoding and that put us to the encoding section

If the keys were damaged or lost the internal storage of the native phone shouldn't boot too, right ?
However, the internal storage works fine and only the SD is not recognizable reporting 0 files (but keeping the total of GB that are used even if it doesn't report files)

How do you think i can decrypt the SD when i don't have the option in security ?

 

[B. Diddy]

I'm not a super-technical person, but what I understand is that the card gets encrypted when formatted as Internal Storage, and if that encryption key is lost, then the card is useless. The phone should still be able to boot and function at a basic level, since the system apps and preinstalled apps are already on the physical Internal Storage, while any apps you installed have more chance of being on the SD card.