Grub boot to Windows 11 fails

Ask Fedora
,
1

I have a machine the had Windows 11 Pro installed on a SSD.
I installed Fedora KDE Plasma 44 desktop to a separate SSD, using the whole drive.
When the grub menu comes up booting into Fedora works fine.
Selecting Windows generates this error:
error: ../../grub-core/commands/search.c:grub_search_fs_uuid:527:no such device: ####-####.
error: ../../grub-core/fs/fshelp.c:find_file:257:file ‘/efi/Microsoft/Boot/bootmgfw.efi’ not found.

Press any key to continue…

I tried using
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
and it says it found the Windows install, it does appear in the grub menu, but generates the error above.
I have not been able to find any “Fast boot” option in Windows.

Entering the Boot Menu in EFI and selecting Windows, starts up windows just fine, but that’s a cumbersome way to boot into Windows.
Can the grub menu be fixed?

3

https://discussion.fedoraproject.org/t/windows-with-encrypted-disks-bitlocker-cant-be-booted-from-the-grub-boot-menu/72635/7

4

In this discussion:
https://discussion.fedoraproject.org/t/cant-boot-to-windows-11-from-grub-menu-with-secure-boot-enabled-dual-boot/198586/8
the OP seems to have found another workaround, but my depth of knowledge of Linux is not sufficient to comfortably grasp his tweak.
Background: decades ago I worked some in Unix. I’ve done enough in BASH that I am able to use it reasonably well. But the Linux configurations and inner workings , not so much.

5

Because GRUB reports “no such device”, it’s likely that its search for the Windows EFI partition fails before it ever loads bootmgfw.efi. Run sudo grep -A15 "Windows Boot Manager" /boot/grub2/grub.cfg and note the UUID after --fs-uuid --set=root, then run lsblk -f and check that it matches the vfat partition on the Windows SSD. At the GRUB menu press c, run ls, then run search --fs-uuid followed by that UUID. If ls lists only the Fedora SSD’s partitions or the search prints “error: no such device”, turn off Fast Boot in the firmware setup so both SSDs are initialized before GRUB starts.

Drafted with AI.

6

UUIDs matched. Found the ‘Fast Boot’ option in the firmware setup, it WAS enabled, disabled it, and now Windows boots from the GRUB menu!!
Thank you!
I had looked for the ‘Fast Boot’ option before, but I thought it was a Windows setting, not a firmware setting.
So nice to have it working.

7

There are two :slight_smile: “Fast Boot” in the BIOS and “Fast Startup” in Windows. It’s good to disable both when dual booting.