su -
vim /boot/grub/custom.cfg
(should be a new file)- Add the following snippet:
#This entry should work for any version of Windows installed for UEFI booting
menuentry "Windows (UEFI)" {
search --set=root --file /EFI/Microsoft/Boot/bootmgfw.efi
chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}
:wq
reboot