Well today was a very very long day. I shot at least 600 shots and every 5 photos I would get error 99. I had to take both batteries out the grip and put them back in each time to get it to work again. 5 shots later, same thing. So this happened at least 150 times today making the shoot very tiring. Things I've tried; Different lenses Cleaned the lens contacts Different cards Different batteries No grip No lens Flash No flash On board flash Resetted settings It was fine last night. I was shooting fireworks and I had no problems. It rained very lightly before the fireworks but the camera functioned perfectly. I cleaned my sensor this morning and that seemed to be normal. However, now when I go to the sensor cleaning function and turn the camera off/on it still says "CLEAn" so I have to take the batteries out to fix that. It still takes photos, just 5 of them. I'm guessing something is really screwed up and its off to Canon for 15 months while they dust for prints.