I have the same Canon Digital Rebel XT black body with 28-55 lens camera and just spent a week in Bryce, Zions and Grand Canyons at over 95 degrees in direct sunlight, taking a little over a thousand pictures and never had a problem, I wonder if it is just a certain factory-run of the camera, or maybe caused by the Card...I use Kingston CF cards. Or maybe the brand of battery-- I can't remember if I using my Canon-supplied one or the generic extra one I bought. But you might consider the battery or flash card as a possible cause. Good luck. Tabitha
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