Does the camera take photos in P mode or Av mode? Does the camera show you an F-number or is that box on the LCD screen just F---?
A reset to factory settings should remove any setting that might be blocking Auto mode.
Originally posted by hr21 Just goes into bulb mode or manual mode on each of them.
Bulb or manual? Usually if the lens is not communicating with the camera, its modes default to M and Av mode, not Bulb (though, Bulb might be available)
Anyway, yeah, press the lens dis/mount button, take the lens off, inspect the mounts to see that it is free of damage or grime or dust. Check both lens and camera mount. Next, mount the lens and make sure it clicks into place. New lenses sometimes need a little more force, but there should be a Click sound.