I'm busy putting an cfw on my friends 3ds, but I came to a slight problem. After going for the nand backup it gives an error on his SD card. It kept doing that even after formatting etc... So I decided to use one of mine to make the backup. Before I continue is it even safe to do? I know I've had this error myself when I first started but I fixed it after a bit of tinkering. Should I continue using his SD card for it, or should I use one of mine and then transfer the emunand to be safe?