I was copying files from my MicroSD (Japanese Kingston) to my PC and found many files were corrupted, or so did Windows say because they work perfectly fine on my DS... a few MP3s, pictures and roms just got "corrupted" and unable to copy them back to my pc... I've had this beofre, with a 256mb flash MP3 player, when writing things to it, (insert a period of time), writing more MP3s on it, it happened a couple of times the MP3 player corrupted some of the MP3s. I was wondering if this is the same thing? Should I just format and copy everything back to the MicroSD card everytime when I add a couple of new things? And, does anyone else have this?