---
title: Win10, Grub 2 and UEFI
aliases: /posts/2021-08-08-win10-grub2-and-uefi
summary: >
  I finally got my broken Grub configuration fixed. Booting Windows from Grub
  wasn't very hard back in the days, but the old "version" doesn't work with
  the newer **UEFI**-typed computers. Now... looking at it... it does not look
  very complicated either ;-)
date: 2021-08-08
categories: [computerstuff]
tags: [linux,windows,grub]

---

Short and concise. I had to deal with a broken Grub 2 configuration recently
and I always had to boot the windows partition from within the BIOS because
Grub wasn't able to boot it right away.

But I researched a bit again and found this:

<https://www.aioboot.com/en/boot-windows-grub2/#UEFI>

I tried this and was instantly happy again because my computer was able to start
into Windows 10 again (without the need of telling the BIOS to start from a
specific disk).

My laptop runs Arcolinux, so to configure Grub I had to find the specific files.
It is `/etc/grub.d/proxifiedScripts/custom` -- which could be also configured
in the app `grub-customizer` (I found that out when I already modified the file).

Not sure what script would load the script when updating the grub configuration
in `/boot` I applied the configuration within `grub-customizer` and restartet
the computer.

The plain file in `/etc/grub.d/proxifiedScripts/` looks like this:

~~~cfg
# file: "/etc/grub.d/proxifiedScripts/custom"
#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry "Windows 10"{
        search -s root -f /EFI/Microsoft/Boot/BCD
        chainloader /EFI/Microsoft/Boot/bootmgfw.efi
        boot
}
menuentry "Reboot"{
        reboot
}
~~~

And/Or if you just want to use `grub-customizer`: go ahead, create the
menu entry and insert the part from above (Windows 10).

{{< figure src="grub-customizer.png" alt="example screenshot" caption="Grub-customizer" >}}

Save and apply the new configuration, reboot and enjoy the comfort.