Write Protected/Memory Card

Hi,
Im trying to copy pictures from my computer on to my memory card. The card is brand new. A message comes up and says "Cannot delete the file. The disk is write protected. Remove the write protection or use another disk." << That's what it says when I try to delete the ones I already have on my memory card. I'm so confused I am clueless as to what to do. Please help if you can. I basically want to pull the memory card up on my computer and delete whats on there OR add new ones and I get the same message. If I put the card in my digital camera and delete individually, it works. Also, I tried to put a picture on the small disk thats in my cell phone and it says thats write protected as well. Thank you for any advice.