#5. "RE: AF-S 55-300 lens on D3100 "lens not attached" message" In response to In response to 3
Since another lens works on your camera, there must be a problem with that copy of the 55-300mm. Exchanging it for a new one makes the most sense. A wire or electrical connection in the lens must have broken or worked its way loose during shipping. Good Luck and Enjoy your Nikons!