I tried to format the SD card in Windows, but the problem is that these methods don't really format it, and there are still some files. When I try to format it with my Steam Deck, a message says Steam Deck can't format the SD card. Why is this? How can I solve this problem?
Steam Deck works under the LINUX environment and uses ext4 as its partition standard. The ext4 file system is suitable for LINUX because it is compatible with UNIX file and folder permissions. Windows and Nintendo cannot receive and use this system. So, the SD card can't show up on Steam Deck if it uses NTFS or FAT32.
Of course, it is also possible that your SD card has suffered physical damage. Sometimes, when a card is heated or hit hard, parts on its PCB can be permanently damaged. If it is physically damaged, you can only send it in for repair. But if you are sure that your SD card is not physically damaged, you can try the method I mentioned below to fix it.
Step 1. Remove your SD card from Steam Deck
The first thing you should do after getting this error is to remove the SD card from your Steam Deck device and place it on your PC.
Step 2. Use your PC to format the SD card in FAT32 format
Now, try formatting your SD card with your PC to see if it works with the built-in formatter. If it still doesn't work, it is recommended to use the Qiling Disk Master to format it. This third-party software supports ext2/3/4, exFAT, FAT32, and NTFS, so don't worry about its compatibility.
Download this tool and click the link to learn how to format an SD card for Steam Deck.
Step 3. Put the SD card back into your Steam Deck
Once formatting is complete, you can place the SD card back into the Steam Deck. Before that, make sure the slot is clean, and the SD card's gold contacts are free of any damage or dust. This may fix the problem, and you will be able to use the card normally again.