It was bound to happen at some point, but after ten years of using Canon products with no problems, I was a bit shocked when the dreaded error message 99 popped up on one of my 40D camera bodies. Removing the battery, and turning the camera on and off helped for a second, but then it happened again, and again, and again. I called Canon's support, and spoke to a very nice agent who asked me to try a few things. "First, use an eraser to remove any possible residue on the copper contacts of the lens. Next, try a different lens, battery and CF card, and if the problem persists, it's time for service". So I followed her suggestions hoping for the best, but it was not meant to be. The error message persisted.
As a CPS (Canon Professional Service) member, the turnaround time for a repair is only supposed to be a few business days. If you're not familiar with CPS, there are three levels of membership, silver, gold, and platinum. I have the silver, which is free as long as you have two qualifying camera bodies and three professional lenses. They provide a list of qualifying gear here. If you are a Canon shooter, I would highly recommend spending the 15 minutes it takes to register.
My next step is to ship the body to Canon's New Jersey service center with tracking, and insurance. Since the camera is not under warranty, they will email me with an estimate.
Thankfully, I still have my other 40D, and an old 10D I can use in the meantime. If nothing else, I hope this post helps other photographers realize the importance of having backup bodies. Hopefully I'll be able to report a happy resolution to this situation soon. More to come.