microsd card contence does not show up on wii?????

hi um i have a 2 gig transcend micro sd card and adapter. i did everything that all the other forums said but when i click the sd card it comes up empty:(

plz help

btw i have a version 4 wii and am attempting the Bannerbomb hack plz tell me why it wont show up :(

thanks

Make sure your SD card is formatted to FAT(16) or FAT32.