The memory card is full. Transfer pictures to your computer or insert a memory card that has available memory. Camera does not turn on. Batteries are not properly installed. Remove the batteries and install them according to the directions on the inside of the battery door.
Batteries are weak or dead.
Install new batteries or use the AC Adapter. Part of the picture is missing. Something was blocking the lens when the picture was taken. Keep hands, fingers, or other objects away from the lens when taking pictures. Your eye or the picture was not centered correctly in the viewfinder.