FAQ #5: My D100 displays "fEE". What does this mean?
Another easily overlooked problem, but good news, because it is easily solved. The reason you are getting this error, is because you have not set your lens ring to its smallest aperture (highest number) rating. Many 35mm camera users have been perplexed by this little error because they are used to adjusting the aperture of the lens on the ring itself.
hope it helps