How do i revert back from formatting SD as internal storage without losing data?

[21Gabriel21]

Hi, I have a Xiaomi Mi A2 Lite, android version 9 and i just bought a 128 Gb samsung SD card , put it in the phone and formatted it as internal storage without actually having much info about this option , also did the stupid mistake of right away migrating data on it when the phone notified me to do it. It seems something went wrong as the numbers are all weird. If i go to Settings > Storage it already tells me that 82 % of storage is used which doesn't make sense.In Storage i have two options: Internal shared storage and Samsung SD card. The Internal shared storage shows the same numbers as my internal memory used to show which is 64 Gb almost full. The Samsung SD card however shows wild numbers . It says 200 Gb used of 256 GB but the card is 128 Gb then when i press it to see more details it shows that the apps use 68 GB of space but there are 0 apps , 131 Gb for system and seems that only images and videos show a proper storage size. In the File Manager only Samsung SD card is present and in the cleaning tab it shows me 69 GB used out of 125. Can someone figure out what happened? Did the data copy on the SD instead of migrate cause of some error? And is it possible to migrate the data back to the internal memory so i can format the SD as portable storage this time but without having to reset the phone? I read somewhere that if i go to Settings > Storage > Internal shared storage and choose migrate data that should free up the SD so i can format it again but when i do it i get the error of not having enough space. Can someone more knowledgeable help me out with this ? Thanks

 

[Rukbat]

Since the format of the SD card is totally non-standard (and encrypted with a key based partly on the serial number of the phone), there's not much you can do. Format the card as an external SD card and store your data (pictures, videos, music, etc.) on the card.

Using the card as internal storage has 2 problems:

1. If the card ever goes bad, you have to factory reset the phone. (Doing an exact location-by-location copy of a bad card is impossible.) Apps don't store on the file as files, they store as used space, but with no directory entry on the card. Directories are in internal storage.

So when the card goes bad, pieces of the app are on the card, but you lose them. You can't "re-install" the app because it's already installed. But you can't uninstall it because Android checks for all the pieces of the app and, when it finds pieces missing, refuses to uninstall what might be pieces of another app written to a location that an uninstalled app used to occupy. Rock and a hard place - so you end up doing a factory reset.

2. All Android apps have to keep their current state saved (in storage) at all times. Android can kill almost any background app with no notice. When you bring that app to the foreground again, Android loads it from storage and tells it to pick up where it left off. So, to you, it appears as if the app was running in the background - but it wasn't.

An app that changes state often (like a game) can do hundreds of writes per second. And SD cards are rated in number of writes. So you can destroy the SD card in days.

So keep apps in internal storage, and the card as external storage. An SD card is a "write once-read many" device. It's not designed to be written to constantly.

 

[B. Diddy]

Welcome to Android Central! I'm thinking that card may also be counterfeit (i.e., is much smaller than the reported size), which can cause all sorts of glitches and crashes.

 

[21Gabriel21]

Used space increased after migrating data to "internal" SD card

Formatted a 128 Gb samsung sd card as internal shared storage then when phone prompted to migrate data i did , after this my phone is more full than before. Setting>Storage>Internal shared storage shows same numbers as my internal memory showed before which is 64 Gb almost full while Setings>Storage>Samsung SD card shows crazy numbers like 137 Gb used out of 256 and 130GB used for system , 5GB for apps with 0 apps on it etc. How can i format the SD as portable again without having to reset my phone? Is it possible to somehow migrate the system data back to phone storage so i can format my SD without messing up the phone? I would apreciate some help, thanks.

 

[anon(10614692)]

Re: Used space increased after migrating data to "internal" SD card

You can't format the SD card without resetting the phone. You could try backing up your data using whatever software is available for your device or use something like Helium

 

[B. Diddy]

Duplicate/similar threads merged

 

[21Gabriel21]

Hey sorry for duplicate threads , i was getting weird pages after trying to post the questions so i thought they were not posted. Anyways thanks for the answers but i was lucky enough this time around, as i said after migrating data my phone storage seemed even more full than before, it seems due to an error the data copied but didn't migrate so my phone memory still had all the data in it. I just took the chance and formatted the SD as portable after noticing that even when i ejected the SD from the phone the apps sill worked and the phone would still boot which from what i understood shouldn't really be possible with an SD formatted as internal storage. After formatting the SD the phone retained all the data that it had before on its internal memory , all the apps work fine, it boots normally. I'll definitely be more careful next time and once again thanks for the answers. I still have a minor inconvenience with the photos app not showing images from the SD, had this problem since the beginning even with another SD but i think i should start a new thread for that. Right?

 

[B. Diddy]

Ok, glad it's working ok now. I agree, start a new thread for the SD photo issue.