Upgrade SG to XG first boot always failed

Hi All,

This is my first post.

I want to upgrade my box SG230 (UTM9) into XG (SFOS 16.50) after i burn the usb booting in my monitor have error missing ubninit

any idea why this error always appear? i use Rufus 2.16 and Unetebootin to create USB booting CD but still the same results

How much the real size for file HW-SFOS_16.05.7_MR-7-305.iso? 1,4 GB or this is the wrong file?

 i just check from this link https://community.sophos.com/kb/en-us/124588

Many Thanks

Jeremy.P