I was at the woodford folk festival recently (photographic mecca) and was planning on taking some photos of the fire event finale, but was confunded through a camera error which prevented me from taking photos. "Error 99 - Please turn camera off then on and check battery". I did that, but nothing resulted. The click the camera was making as I turned it on sounded like the mirror swinging up, like when you start live view. After changing batteries to no effect, I simply left it off for a day and it has resumed normal function. Has anyone encountered this problem and know anything about its causes/solutions?