My (external) SD card is being weird.

I'm in TWRP, since a Lineage OS dirty flash (one without a wipe first) bricked my phone. Using the TWRP file manager, or the terminal, it doesn't matter, moving files to it fails. Copying files to it fails. Deleting files from it fails. Formatting it fails. mkfs.ext2 from the terminal fails (vseek error). mkfs.fat doesn't print any error, it may be returning a nonzero exit code but I can't check. I've mounted and unmounted it multiple times, it doesn't seem to help.

I've checked, and there's no hardware switch on the external SD card for read-only. Since it's vfat, I've tried fsck.fat to no avail. Mounting it as rw didn't really do anything, everything still fails (it was still mounted as rw afterwards, so it didn't switch into read-only mode). All of that was tested from the terminal.

I'm not sure what's going on. This is a perfectly reasonable SanDisk Ultra MicroSD card, that has worked before. Here's the fsck output (I hit backspace on the first option, sorry for the ^H):

~ # fsck.fat /dev/lock/mmcblk1p1
fsck.fat 3.0.28 (2015-05-16)
1) Remove dirty bit
2) No action
? 1^H2
FATs differ but appear to be intact. Use which FAT ?
1) Use first FAT
2) Use second FAT
? 1
Reclaimed 7 unused clusters (229376 bytes).
Perform changes ? (y/n): y
/dev/block/mmcblk1p1: 310 files, 7718/973584 clusters

My particular phone is a Samsung Galaxy Note 3, Verizon variant. I just rooted it and want to try a clean flash of Lineage OS but I need the ROM on an SD card for that. Either that or I can start a Windows VM to flash a ROM like that.

Edit: Lineage OS works. I was able to install 15.1, Android Oreo 8.1. External SD card still doesn't allow writing, even from inside the OS. Still shows the exact same filesystem.

Still looking for an answer to this question. I'd like to use my 32GB SD card please.

  • Can you write any file on the SD card when using another phone, tablet or PC? Are you able to format it with another phone, table or PC? – Reddy Lutonadio May 31 at 13:07
  • I don't actually have any other devices that accept an SD card. This one came from a phone with a shattered screen. I honestly won't be able to tell if this phone's SD card slot is broken or something. – Dev May 31 at 13:16
  • Have you tried to format from the OS? Does the issue persist? – Reddy Lutonadio May 31 at 16:33
  • @ReddyLutonadio I've tried to format: 1. from TWRP's GUI, 2. from TWRP's terminal, 3. from Lineage's GUI, 4. from Lineage's terminal, nothing works – Dev May 31 at 20:01
  • What about holding volume buttons and power button till you get into fastboot and flashing from there?? – helper Jun 5 at 13:51

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