Cannot upgrade bootloader

Upgrading 15.0 to 15.1 via USB image.

Get the message:

“Cannot upgrade bootloader. The upgrades system uses legacy BIOS boot while the installation medium has been booted using EFI boot. Upgrade may fail or system may be unable to boot following upgrade”

How to i force the upgrade medium (USB Stick) to use legacy BIOS?? (if that is all that is needed here)??


Click on the “Booting” heading. Make sure that it says “grub2” rather than “grub2-efi”.

If that is right, you can probably ignore that warning and tell it to continue anyway. But note that I have never done this on an upgrade, so no guarantees.

Yes, best to boot the USB in legacy mode if you can. Unfortunately, I don’t know how because it varies from computer to computer. You can check if there is a BIOS setting to disable UEFI.

The installation medium boots according to how the UEFI BIOS is setup. It’s up to you determine how to get your UEFI BIOS to boot the installation media in BIOS mode. It may be as simple as making a choice from a BIOS boot menu, possibly the F12, F11, F8, F9 or other key as POST proceeds. You may need to actually go into BIOS setup and find a mode labeled CSM or compatibility or MBR or something other than UEFI.

Yes … i had already reformatted the USB to FAT and rebuilt a boo-table USB with latest 15.1.1 ISO. That worked fine, performing the upgrade without a hitch.

Thanks for the suggestions. :slight_smile: