Create an empty file called ver.req in the root of the flash card. Switch on the Camera and change to review (pictures). Press and hold FUNCSET, then instantly press DISP. Please note that holding FUNCSET for too long (until clock appears) and then pressing DISP won't give the desired results. You should now see the following on your screen: Canon PowerShot SD800 IS P-ID:3136 NT Firmware Ver GM1.00E E18 Oct 4 2006 10:07:45 Pressing DISP once again with FUNCSET still pressed: Adj Ver.006.006 ZoomLensError 2007.07.08 14:16:13 Pressing DISP a third time with FUNCSET still pressed: