Sony A7 IV Unable to update firmware for A7M4

[kenh]

I purchased a slightly used A7M4. Firmware is at 1.2. Looking to upgrade to 5.1. Following the instructions for a card based update, when viewing the version in the Setup section, the Software Update option is not available. Looked for clues or even older firmware updates, but haven't found any indication of solution. Wonder if 1.0.5 update was not applied or applied properly. Looking for guidance for steps.

 

[THXGEEK]

Perhaps a drastic step, but have you considered resetting the camera back to factory defaults?

 

[kenh]

Thanks. I had tried that with the Setting Reset - initialise, but to no avail.

 

[Tim Mayo]

If it's 1.2 you should be able to go straight to 5.01 .. Make sure BODYDATA.DAT is in the root directory of the card, not in any sub-folders. Also make sure your battery is fully charged. The file could also be corrupt, so try downloading it again or downloading from another source.