Card error message during formatting XD pic...

I am attempting to format the XD picture card 1 GB for my parents D-560 Olympus camera. I insert the card in camera, answer yes to formatting, it warns me it will delete all memory (which is fine bc nothing has been saved to the card). Then it gives me a card error message. Help, what do I need to do to get the card to work? I bought a xd M2GB card months ago and just decided to use it on my C-50 zoom Olympus Camera. I tried to format in the camera as asked and got Card Error! I formatted on computer using my card reader but got same error when inserted into camera. And it wanted me to format again. I just bought a M+ 2 GB card which is supposed to be compatible and it's the same problem all over again. Help - c