Windows boot not showing in grub (ubuntu/windows dualboot)

grub_fix.md

Grub menu fix for Windows / Ubuntu dual boot

Use this if boot repair does not fix the issue.

adapted from: https://askubuntu.com/questions/197868/grub-does-not-detect-windows

Make sure Windows is installed and the .efi file exists

sudo os-prober

Get UUID of Windows partition

sudo blkid /dev/<windows partion> #eg: sudo blkid /dev/sda1

Add the following to /etc/grub.d/40_custom

menuentry 'Windows 11' {
    search --fs-uuid --no-floppy --set=root <partion UUID>
    chainloader (${root})/EFI/Microsoft/Boot/bootmgfw.efi
}

Update grub

sudo update-grub