A few links that might help those struggling with this issue: How to update latest MacBook pro EFI firmware manually? https://apple.stackexchange.com/questions

A few links that might help those struggling with this issue: How to update latest MacBook pro EFI firmware manually? https://apple.stackexchange.com/questions/311947/how-to-update-latest-macbook-pro-efi-firmware-manually https://apple.stackexchange.com/questions/311947/how-to-upda... Is it possible to install flash firmware update without having access to OSX? https://apple.stackexchange.com/questions/115354/is-it-possible-to-install-flash-firmware-update-without-having-access-to-osx https://apple.stackexchange.com/questions/115354/is-it-possi... Flash EFI firmware update manually on a Mac(Book 5,1) https://pubmem.wordpress.com/2011/04/09/flash-efi-firmware-update-manually-on-a-macbook-51/ https://pubmem.wordpress.com/2011/04/09/flash-efi-firmware-u... Which EFI firmware should your Mac be using? (version 3) https://eclecticlight.co/2018/10/31/which-efi-firmware-should-your-mac-be-using-version-3/ https://eclecticlight.co/2018/10/31/which-efi-firmware-shoul...