Hello,
in that case the card seems to be write protected. In that case the only thing you can do with the card is to try it with another pc to see if there its also write protected. If yes then the card is defective and needs to be replaced
you can ask Sandisk for replacement under the following link
http://kb.sandisk.com/app/rmaform/session/L3RpbWUvMTQ0MDU3NzcyOS9zaWQvcGluTlZTdW0%3D
