I recently bought an SD card for my 3DS, and after using it to back up some save data, I found that it erased everything when I put it back into the console. When I connected it to my Mac, most of the folders were gone except for the "Nintendo 3DS" folder. I attempted to format it using Disk Utility, but the process got stuck with no errors showing.
Thinking it might work better on Windows, I tried using Rufus, but although it managed to format the card, neither Windows nor macOS could recognize it afterward. I wanted to see if the 3DS could format it again, but now the console won't boot with the SD card in it.
I even tried the "SD Card Formatter" tool on macOS, which gave me several error messages, including issues with the boot sector and invalid arguments. At this point, I just want to completely format the SD card and avoid using it with the 3DS again—I'm selling that console as I'm really frustrated with it.
4 Answers
Just a heads up, the 3DS and its SD card format can be tricky. It’s a bit outdated and proprietary. If you plug it into a PC, it can cause various issues, so it’s not surprising you’re running into trouble now.
You might want to give the official SD Card Formatter tool another go, found at sdcard.org. If that doesn’t work, your card could be damaged.
That's the SD Card Formatter I already tried, and it didn't help!
It sounds like your card might be on its last legs if no tools are recognizing it properly. If all else fails, consider replacing it.
Actually, the format used by the 3DS is just standard FAT32, not proprietary. However, the way it handles files might be specific to Nintendo systems, which can complicate things.
I get that, but I've used this SD card many times between my computer and the 3DS before. It's frustrating that it's acting up now!