I'm having problems with my new SD Card?

I just bought a new 8 gig SD Card but never used it. When buying SD Cards I format my card in my camera before taking pictures with my Nikon D3000. The problem I'm having is simple. The camera took pictures wonderfully and I'm now on my computer and having it say I need to format it. I keep saying no but never had this problem before. If I format the card now I will loose all my pictures. How do I fix this problem and view my pictures on my computer, so I can fix them up or upload them to a selling site.

Upload all those photos. Pull the card and format it in the camera - after making sure your photos are safe.

Pop it back into the camera, if that can still read it the problem is with your card reader

Are you putting the card into a card reader on your computer? If so, and you have an older computer, it may not read a card that big. I would suggest you buy a card reader---less than $10, and use that instead. Just plug the reader into a USB port on your computer, and then insert the card into the reader. That is the way I always upload my pictures, as do many of the people on here.