Right-click the SD card and click Change Drive Letter and Paths. After this, you can try again to see whether you can open it or not. nro to the switch folder on your SD card If you were already using your microSD card as a storage device for your games and backed up the Nintendo folder before partitioning your microSD card, please place it back on the root of your microSD card. If you have a micro SD card that shows as locked, the fix is to borrow or buy an SD card adapter. )Switch off phone and boot in Recovery (you should know how to). Replace h with your SD card drive letter.