I've seen it on a number of games, My Sims, Animal Crossing, etc. On this one card, it will put up a screen with the game's artwork style, saying it cannot load. I tried the card in two different DSes/Simplies, same thing. It's not the ARM7 deal, as just copying the file to a different microSD works fine. All I have been able to deduce is it's some kind of problem on writing. One a file starts with this error, it will always do it. But most of the files on it work just fine. I guess there's a few bad bits in there somewhere. I just didn't think it would wear out in under 6 months.