Pokémon Sword & Shield is out! That’s great. What’s not great is that some people’s games are crashing. That’s bad enough, but what’s worse is that some players are also reporting a catastrophic failure that corrupts their Switch’s SD cards and eliminates gigabytes of data.
But before you panic, this issue appears to be rare. You probably have never even experienced a crash at all, and if you have, it likely didn't result in the wiping of your save files as reported by some of the earlier tweets on this issue. We can't blame folks for wanting to warn others, but it's important to get the right info out there.
Game crashed on an attempted autosave (or at least I assume so), I then the game crashed on boot to I put in my smash cart to test, smash crashed on boot too, so I rebooted my Switch.— DeathChaos (@DeathChaos25) November 15, 2019
Now everything on my Switch looks like this, even the cart games are asking for a redownload... pic.twitter.com/OEFHZErLCx
Thankfully, this Reddit thread seems to do a great job of collating the current info. Initially, it was said that peoples' save data was getting corrupted, but that was quickly corrected to be just the SD card. And then the thread turned to Switch hacker and Pokémon data miner extraordinaire SciresM to get the real low-down on what's going on.
“Basically, the operating system tries to retrieve data from disk, and that fails,” said SciresM, going on to explain how this results in the Switch crashing and requiring a restart.
But the crash isn't coming from Sword & Shield, as many people thought. It actually has to do with the file formatting on the Switch's SD card.
The glitch is centered around the exFAT file format. Many of the newer SD cards use this filing system to save data, where older cards use FAT32. However, exFAT drivers have been known to cause issues and get corrupted on the Switch. If that happens, the entire SD card will need to be reformatted.
Also, to be explicit: save data is not at risk at all. Saves are stored on the internal NAND, which uses FAT32/doesn't corrupt.— Michael (@SciresM) November 15, 2019
The only data at risk are downloaded games/other SD card files, and those can be redownloaded.
The absolute worst case is you lose some screenshots.
Reformatting anything causes all data on the drive to be lost, meaning you'd lose any data stored on the Switch SD card. Save files, fortunately, are saved on the Switch's internal drive and should be safe from this error. At worst, you’ll lose a whole bunch of saved games but you’ll be able to download them again later.
The solution to the problem is to head it off at the pass. Instead of waiting for the SD card to become corrupted, back up your data and reformat the SD card to use FAT32 instead of the exFAT file format. That should inoculate your Switch from this issue.