I keep clicking the power button but my camera just won't turn on.

One of my buttons just won't work. I keep clicking it, but nothing happens. Other buttons are still working, though.

Make sure that the camera is turned on and that the lens cap is removed. If you are still having problems, then your camera probably can't take pictures because there is either a problem with the mother board or with the image sensor. In both cases, you may need to replace either of these two parts. Follow the guides on our Nikon Coolpix P500 device page in order to remove your mother board or your image sensor.