Hello. I have a MB-MC512SA/EU microSD card that I’ve been using as an external portable storage for the phone for the past ~2 years. The phone had previously formatted the storage device with the exFAT filesystem. However, I have been having write issues with the card’s filesystem recently where it frequently became read-only when trying to write multiple files simultaneously, which necessitated reboots to get it to be writeable again.
As such, I have made a block-level backup of the storage device using ddrescue and have manually reformatted with the ext4 filesystem using mkfs.ext4, as I believe that it is a more robust filesystem than exFAT and that Android fully supported the filesystem. Afterwards, I manually copied over the files from the backup to the new filesystem.
However, upon reinserting the card and rebooting the OS, it seems like the phone incorrectly recognises the storage device as corrupted (“This Samsung SD card is corrupted” displays in the storage settings page), even though it isn’t actually, as I can read and write data to it fine on my Linux system.
I have tried manually using the mount tool on Termux to mount the storage device, but this predictably fails as I don’t have root access.
As such, does anyone know how I can go about getting this set up to work, preferrably without having to root the phone (I’d like to continue being able to use it for mobile banking, which I’ve had issues with on previous rooted devices).
For context, I am currently on build number FP5.UT2M.B.113.20250319 of the official OS.