A friend of mine showed me his Canon 20D. The "ERR 05" message was flashing on the camera. The user manual said that this indicates a malfunction with the pop-up flash. The camera will operate just fine, unless you press the button for the flash to pop-up (or if in the automatic modes, if it thinks it needs the flash). Has anyone run into this before? Are there instructions anywhere on steps I could take to find and fix the problem, or will a technician need to look at it?
There is a screw on both sides that fasten a bracket that lifts the flash. One of the screws may have come loose and may be jamming the latch. If you can get it open, check for missing screws and also check to make sure the latch moves freely when you push it with your finger.