This is the link to Nikon Europe's English site: http://nikoneurope-en.custhelp.com/app/answers/detail/a_id/65374 This is their description of the problem: We have confirmed that with autofocus shooting using the AF-S NIKKOR 200-500mm f/5.6E ED VR lens, autofocus may sometimes become disabled and focus operation switches to manual focus* when the zoom ring on the lens is rotated while the camera's shutter-release button is pressed halfway, or the camera's AF-ON button is held down. Firmware in lenses with a serial number of 2008365 or higher have already been updated.And Nikon needs to update the firmware on the lens. The problem is that Nikon is not yet able to let the user update the firmware on a lens, as they can do on digital camera bodies. I think it should be possible to do so via a camera. However, at this point, it means shipping the lens back to Nikon for firmware update. Please keep in mind that those are European serial numbers. Nikon USA's versions seem to have a serial number that starts with a 6.