I had a dualboot system up and running for a long time with Ubuntu 22.04 and Windows 10. However, after updating Ubuntu to 24.04, I cannot boot into Windows anymore. Both Windows and Ubuntu are on separate disks.
When I select the Windows disk in the GRUB menu (visible since I use os-prober), the following error messages are displayed:
error: no such device: /EFI/Microsoft/Boot/bootmgfw.efi.
error: file `/EFI/Microsoft/Boot/bootmgfw.efi' not found.
When mounting the Windows disk (only possible with read-only mode, as Windows is in hibernation), the bootmgfw.efi file is found multiple times, e.g., in /Windows/Boot/EFI/bootmgfw.efi or in ./Windows.old/Windows/Boot/EFI/bootmgfw.efi.
How can I make GRUB find this file? How can I restore my Windows boot option? I guess it has something to do with UEFI and GRUB, but I am too stupid to understand it properly.
What I tried and did not work:
- Disabled fast boot and secure boot
boot-repairgave me: "LegacyWindows detected. Please enable BIOS-compatibility/CSM/Legacy mode in your UEFI firmware, and use this software from a live-CD (or live-USB)", find the whole boot-repair paste here- Booted from a live Windows stick and
Repair your computer > Troubleshoot > Startup Repair - The other solutions from the various askubuntu threads (for instance this) are not working either
