Try one or more of the following:
- Press the shutter button all the way down.
- Make sure that the camera is not in Favorites mode (certain models only). Turn the camera off then on again.
- Insert a charged battery.
- Wait until the AF/AE indicator turns green before attempting to take another picture.
- Transfer pictures to the computer, delete pictures, change the image storage location, or insert another memory card.
See your camera User's Guide for more information.