SD Card?

[blasteryui]

So my card was perfectly fine, card is brand new, when I put the card in my milestone xt701, it says preparing, and then that goes away, but under settings it says unavailable space etc, when I go in camera mode it says insert sd, yet when I run SNES emu, I can run roms off the card.. on top of that, when I plug in the card into my pc it reconizes it perfectly fine, how do I fix this, its really annoying