When I get odd things going on like that I head to the factory reset or reset (different cameras name this differently) so I'm sure the settings in the camera are stock. After the reset I try again.
There is a thing about auto focus that needs to be written here. It takes some light to accomplish auto focus. Be sure it's not a dark night scene.
Have a weird problem with my camera. Camera has standard nikon 18-55 mm lense. Have used it for years with no problems. Now if the lens is set to anything beyond 30mm or so it won't take a picture unless the lens is set to manual focus (no attempt to focus and back screen goes black when shutter button is depressed). Between 18-30th it will operate normally on auto focus mode and take pictures. 70-200mm lens also works fine.

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