Every time you insert your card into the camera, you should format it in the camera. Many times, errors occur when you remove the card from the camera and insert it onto a PC, which could write junk onto the card that the camera cannot understand. Each time you pull the card from the camera and replace it, you compound the chance that corruption will occur. Nikon provides a menu command ( and dedicated buttons on some bodies ) that will format the card in the camera, which will minimize the number of memory card related issues you'll encounter. I know this doesn't help your current problem, but could minimize future problems. I originally found this solution on Ken Rockwell's site in his D90 user's guide, but the tip is also found here Rockwell Pro Tip about Formatting Memory Cards
I have witnessed this corruption several time personally, and have not seen it since I've started with the format card on every insertion policy.
I also wouldn't assume the card is bad until I tried the formatting. A class 10, 32gb card cannot be that old, and is not cheap. I still use 4gb trancend cards that are probably 3 years old and see heavy use without issue.