[SOLVED] How to format SD card that has been formatted as internal storage for Android?

[toward]

My SD card was formatted as internal storage for Android 6.0 and it was working fine. I mounted my SD card on my second Android phone and format it as external storage but again it said “Unsupported SD card”. So I mounted my SD card on my PC and I tried to format it using Windows 10 but it failed (“Windows was unable to complete the format”). I have tried clean all command in Diskpart and it took an hour to be completed but at the end nothing has changed. It has two drives: 16MB and 59GB drives. I guess the SD card is locked or encrypted by Android. When I try to delete the partition by fdisk in Linux, it will show a successful result but unable to create a new partition due to insufficient memory in virtual disk drive. I have followed this answer to unlock the SD card but the status shows that the SD card is unlocked. I have tried GParted as well but no luck. Is there a way to reuse my SD card as a portable storage?

GParted details when I delete the partition:

GParted 0.30.0 --enable-libparted-dmraid --enable-online-resize



Libparted 3.2



Delete /dev/mmcblk0p2 (unknown, 59.46 GiB) from /dev/mmcblk0  00:00:08    ( SUCCESS )



calibrate /dev/mmcblk0p2  00:00:00    ( SUCCESS )



path: /dev/mmcblk0p2 (partition)

start: 34816

end: 124735454

size: 124700639 (59.46 GiB)

delete partition  00:00:08    ( SUCCESS )

libparted messages    ( INFO )



Input/output error during write on /dev/mmcblk0

========================================



Delete /dev/mmcblk0p1 (unknown, 16.00 MiB) from /dev/mmcblk0  00:00:01    ( SUCCESS )



calibrate /dev/mmcblk0p1  00:00:00    ( SUCCESS )



path: /dev/mmcblk0p1 (partition)

start: 2048

end: 34815

size: 32768 (16.00 MiB)

delete partition  00:00:01    ( SUCCESS )

========================================

GParted details when I try to format:

GParted 0.30.0 --enable-libparted-dmraid --enable-online-resize



Libparted 3.2



Format /dev/mmcblk0p1 as fat16  00:00:01    ( ERROR )



calibrate /dev/mmcblk0p1  00:00:00    ( SUCCESS )



path: /dev/mmcblk0p1 (partition)

start: 2048

end: 34815

size: 32768 (16.00 MiB)

clear old file system signatures in /dev/mmcblk0p1  00:00:00    ( SUCCESS )



write 512.00 KiB of zeros at byte offset 0  00:00:00    ( SUCCESS )

write 512.00 KiB of zeros at byte offset 16252928  00:00:00    ( SUCCESS )

write 4.00 KiB of zeros at byte offset 16711680  00:00:00    ( SUCCESS )

write 8.00 KiB of zeros at byte offset 16769024  00:00:00    ( SUCCESS )

flush operating system cache of /dev/mmcblk0  00:00:00    ( SUCCESS )

set partition type on /dev/mmcblk0p1  00:00:01    ( SUCCESS )



new partition type: fat16

create new fat16 file system  00:00:00    ( ERROR )



mkfs.fat -F16 -v -I '/dev/mmcblk0p1'    ( EXECUTING )



Failed to execute child process “mkfs.fat” (Input/output error)    ( ERROR )

========================================



Format /dev/mmcblk0p2 as fat32

Results for zeroing:

sudo dd if=/dev/zero of=/dev/mmcblk0 bs=8192



dd: error writing `dev/mmcblk0`: No space left on device



7795969+0 records in

7795968+0 records out

63864569856 bytes (64 GB, 59 CAB) copied, 3824.26 s, 16.7 MB/s

Results for amd64-stdtool status:

[+] Found RCA for /dev/mmcblk0: E624.

[+] Card CSD: 400E005A7B590001DED48F700R808006.

[+] Write protection state: Off.

 

[TerryLaze]

My SD card was formatted as internal storage for Android 6.0 and it was working fine. I mounted my SD card on my second Android phone and format it as external storage but again it said “Unsupported SD card”.

If it stopped working out of the blue on the original device then chances are very good that the SD card just failed,If the sector that holds the partition info can't be written to anymore,because of wear or anything else, you can't change the partitions anymore.

 

[alceryes]

'Clean all' writes zeros across the drive so yes, that would take a while. What if you just use 'clean'? Can you then create a simple volume in diskpart or disk management? Some SD cards have a physical write lock switch. Is the card locked?

As @TerryLaze says, if you can't even clean it then it's probably bad.