Hi,
I had the same error reading on my Fuji. Basically I was told that if you initialise the card it wipes it clean. I could not upload it onto a pc but a photograpic studio ran it through a system recovery program and was able to retrieve the images and put them on a CD. (This cost very little and you could probably do it yourself if you downloaded the software from the net).
Then the card was initialised and usable.
I think that error occurs if the camera is switched on or off during the uploading/printing process.