Recently my Nikon d3000 started the 'lens not attached' error. I have two lenses, neither of which work. I tried the lenses in another camera body, and they work fine. I have cleaned the contact points and tried reattaching the lens, making sure the lens is connected, and nothing works. Any other suggestions? The warranty ran out about a week prior to this happening.
Well, if you have already cleaned the contacts (how have you cleaned them? I would have adviced ethanol on a smooth and clean material...), you have almost no choice left: you need to bring your camera body and optics back to the shop you bought them to or to refer to the Nikon customers service. Sorry...