[Mashiro]

Take backups of the data that you stored on the SD card ASAP if you value what is on it.

I will stick my head wide out the window and say it is a hardware defect.

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Nonetheless you can try a few things out and see if they bear any success.

1. Actually make sure the hardware "read only" switch that exists on SD cards isn't enabled.

2. Try to remove the read only attribute (if Windows somehow decided to mess up and set it for the SD card).

1. Connect the ”Read Only” storage device such as an SD card, USB, external hard drive  to your PC
2. Open a Command Prompt by typing: command in the Search tab, click Command Prompt
3. Type: diskpart and hit Enter
4. Type: list disk and hit Enter
5. Type: select disk 0 and hit Enter (0 will be the drive letter of your read-only hard drive/USB/SD card, etc.)
6. Type: attributes disk clear readonly and hit Enter
7. Type: exit and hit Enter to finish the process

3. Check the filesystem of the SD card and let it be repaired (chkdsk and such).

4. Backup data and try to format it and see what happens.


If this has no success it is more of a sign that there is a hardware defect such as the flash cells being broken and turning read only or the controller being broken.


Being honest, all attempts to save the card are worthless. Save all data you can first and then you can play around with it as much as you want but I highly doubt you will be able to do anything if all above attempts failed.