Be sure to copy any files off your card
before you format it, 'cause they'll all go bye-bye if you don't.
To format, just right-click on the drive icon (whichever one your card shows up as) and choose format. Under the File System option, choose an FAT option, and then let it run. You can add a label there too, if you like.
Do be
sure you select the
right drive!