On Jan 15, 2022, at 07:25, Patrick O'Callaghan <pocallaghan(a)gmail.com> wrote:
I have a laptop as a secondary machine, using F35. I've reluctantly had
to install Windows 10 on another partition, and of course Windows has
stamped all over the boot block in its usual arrogant way so I can no
longer access my Fedora installation (though it's still there).
What's the quickest way to get Grub back, with the Windows boot as an
option? Can this be done from within Windows or do I need to boot a
rescue drive? Both systems use UEFI.
The great thing about UEFI is that it doesn’t involve boot sectors anymore, it’s just
files in the EFI volume and entries in the boot firmware.
You should be able to go into your BIOS boot menu and choose the Fedora boot entry and it
should boot just fine, unless the windows install formatted the EFI volume, but it
shouldn’t by default. You can also boot off a live USB and use ‘efibootmgr’ to change the
boot order.
Be sure to turn off Fast Reboot in the Windows settings. That setting bypasses the normal
firmware boot and you won’t see the Fedora bootloader.
—
Jonathan Billings