Hi All,
Short version: I fixed the problem by reformatting the drive.
Long Version:
My SanDisk Cruzer Glide 32GB became read-only on Linux systems and would not even mount properly on Windows (i.e., no drive letter was assigned to it when I plugged it in; it was still recognized in the device manager as a USB mass storage device, but I couldn’t access it). After some poking around, I decided to try to completely reformat the drive on Linux.
I used KDE Partition Manager on a Lubuntu 20.04 installation, but I think gparted or fdisk would work just as well. You can find tutorials for all of these online. You may be able to do basically this same thing from Windows in the command line using the diskpart utility–there are plenty of tutorials and youTube videos for all these tools.
Here’s what I did:
NOTE: THIS WILL DELETE ALL THE FILES ON YOUR USB. I SUGGEST BACKING THEM UP TO A DIFFERENT DRIVE BEFORE CONTINUING
Step 1
Launch the KDE Partition Manager
Step 2
Select the USB device you want to format under the “Devices” section.
Step 3
If any of the partitions in the table on the right show a mount point (something like “/media/home/CRUZER”), right click the partition and select “Unmount”. Do this for each mounted partition.
Step 4
Select all the partitions on the USB and click the delete button. This won’t delete all the partitions yet; it’ll just put the delete command in the queue under “Pending Operations”.
Step 5
There should now be only one partition showing in the table named “unallocated”. Select it and click New.
Step 6
In the popup that comes up, select the settings you want for the USB. I’m using mine primarily as removable memory for my Linux system, so I went with the ext4 file system. If you’re using Windows, FAT32 is probably your safest bet if I understood the rest of this thread. If you’re using the stick with cameras, you’d have to check which file systems your camera is compatible with.
Partition type: Primary
File system: ext4
Encrypt with LUKS: No (unchecked)
Label: (blank; this is the name of your USB stick)
Free space before: 0.00 MiB
Size: Click the up arrow until it maxes out. This will be less than your actual USB memory capacity since some of the storage space is reserved for firmware (I think)
Free space after: 0.00 MiB
Step 7
Click “OK”. This will add “create a new partition” to the Pending Operations queue.
Step 8
Click Apply. It will probably take a few minutes.
After that you should a blank and writeable USB stick again. Mine worked without any issues on my Linux installation, and Windows gave me the expected “unsupported file system” error, asking me if I wanted to reformat the drive (which is a good sign).