I have tried to update from 2.1.1 to 2.1.2 but the update program hangs at 99%. No matter what I try I can't exit the program or go back to the previous version. Now the camera just asks to update each time I restart or replace the battery.
Thats not good ! They warn fron that, if the updating process is interrupted that can cause camera failure. Contact your nearest canon dealer for support.