I was running into the exact same issue as you just earlier.
As the other comments have said, disable secure boot and try again (also remember to follow the battery instructions for being less than 100% charged before plugging in to update). I personally ended up going the USB route which works as well—download the EFI update and boot from disk in F12 menu just like when installing Fedora/Ubuntu.
I was running into the exact same issue as you just earlier.
As the other comments have said, disable secure boot and try again (also remember to follow the battery instructions for being less than 100% charged before plugging in to update). I personally ended up going the USB route which works as well—download the EFI update and boot from disk in F12 menu just like when installing Fedora/Ubuntu.