open the card door and remove the card from the camera ( do not close the battery door also leave the power switch on the camera should stay off).if you see the Firmware Update Program Loading screen, it means you have opened the battery door a bit too late wait until the camera turns off and try again!.if you did it right, the camera will turn off (wait for a few seconds to make sure it's really off).open the battery door ASAP, but don't remove the battery!.

launch Update Firmware from Canon menu, click OK.Whatever you do, do not remove the battery in the middle of a firmware update! Method B (recommended, one single card required, either SD or CF, source, discussion): If you are running 1.3.3, 1.3.4 or 1.3.5, you can downgrade with EOS Utility ( instructions).ĭowngrading from 1.3.6 is possible, but tricky. Make sure you are running Canon firmware 1.2.3.However, any card configuration may be used. use CF card(s) for taking pictures or recording videos.If you need any of these features, you will have to downgrade to 1.1.3. If you don't need anything from the above list, please consider downgrading to 1.1.3.Ī few ML features are not compatible with 1.2.3 (see the Features tab and the 1.1.3 forum thread). dual monitor support (internal+external).Firmware 1.2.3 is required if need any of those features from Canon:

Magic lantern canon 5d mark iii 1.3.3