Scheduled Maintenance: We are aware of an issue with Google, AOL, and Yahoo services as email providers which are blocking new registrations. We are trying to fix the issue and we have several internal and external support tickets in process to resolve the issue. Please see: viewtopic.php?t=158230

 

 

 

os-prober not detecting windows boot manager

If none of the specific sub-forums seem right for your thread, ask here.
Post Reply
Message
Author
emanuele
Posts: 4
Joined: 2022-08-12 07:46

os-prober not detecting windows boot manager

#1 Post by emanuele »

Hello guys, I am new to debian but not new to linux. I am trying to make os-prober detect my windows partition. I tried mounting the windows efi partition to a folder (which I created) and running mkconfig, I tried adding a manual entry like suggested here : https://unix.stackexchange.com/question ... s-not-show. Windows is installed on a different SSD but I cannot for the life of me understand how to make os-prober detect it. Thanks a lot for the help

Dai_trying
Posts: 1100
Joined: 2016-01-07 12:25
Has thanked: 5 times
Been thanked: 16 times

Re: os-prober not detecting windows boot manager

#2 Post by Dai_trying »

I'm guessing you might be using Debian Bookworm which by default disables os-prober, try adding this line to /etc/default/grub and see if that works.

Code: Select all

GRUB_DISABLE_OS_PROBER=false
EDIT: I should probably add that you will need to update grub and then reboot for this to have an effect.

emanuele
Posts: 4
Joined: 2022-08-12 07:46

Re: os-prober not detecting windows boot manager

#3 Post by emanuele »

Ofc I have os-prober already enabled..

p.H
Global Moderator
Global Moderator
Posts: 3049
Joined: 2017-09-17 07:12
Has thanked: 5 times
Been thanked: 132 times

Re: os-prober not detecting windows boot manager

#4 Post by p.H »

Does Debian boot in UEFI or BIOS/legacy mode (does /sys/firmware/efi exist) ? The system must be booted in EFI mode for os-prober to detect Windows EFI boot manager.
Mounting Windows EFI partition does not help.

emanuele
Posts: 4
Joined: 2022-08-12 07:46

Re: os-prober not detecting windows boot manager

#5 Post by emanuele »

It is booted in EFI.

Anyway I solved by adding the entry manually, I don't know why it didn't work the first time and I don't know why I had to do this but the answer is here :
https://unix.stackexchange.com/question ... s-not-show

Thanks everyone
Last edited by emanuele on 2022-08-12 12:47, edited 1 time in total.

p.H
Global Moderator
Global Moderator
Posts: 3049
Joined: 2017-09-17 07:12
Has thanked: 5 times
Been thanked: 132 times

Re: os-prober not detecting windows boot manager

#6 Post by p.H »

Can Debian "see" Windows' SSD and partitions at all ?
EDIT: you wrote that you could mount Windows' EFI partition so I assume yes. os-prober looks for /EFI/Microsoft/Boot/bootmgfw.efi. Is that file present in Windows's EFI partition ?

Sometimes a NVMe SSD cannot be used by Linux when the SATA controller is set in a proprietary "RAID" mode instead of standard AHCI in the BIOS/UEFI firmware settings.

emanuele
Posts: 4
Joined: 2022-08-12 07:46

Re: os-prober not detecting windows boot manager

#7 Post by emanuele »

The fact is that I am not using a NVMe (unfortunately), anyway the fire bootmgfw.efi must be present because to boot windows I did this :

menuentry 'Windows 11' {
insmod part_gpt
insmod fat
search --no-floppy --fs-uuid --set=root **UUID OF PARTITION**
chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}

So I don't know exactly how this is supposed to work but in some way chainloader takes the efi file of windows in order to boot it, and it works..so yeah I don't understand why I am having this issue. I remember having this issue also on debian stable before switching to fedora (in which it worked) and now I am back (I hope permanently) on debian unstable

Post Reply