Mageia forum

I had a successfully running dual boot system. It had Mageia 7 and Windows 10. Windows 10 was the default boot. Mageia was selected as a boot option during the first 10 seconds of a system boot.

I ran updates to Windows 10. Now I lost the Mageia boot option.

Did you try running the Mageia installation again, which should offer an "Update" installation for the existing install? As you still have a complete installation, just click through it, it should reinstall the bootloader and you should be good to go again.

Do what doktor5000 recommends and install Grub2.
I can add that you will have to start win-10 and disable fast boot, you will gain access to partitions supported by win-10 from Magea-7.

Late to the party, but here goes.

if you have the spare space, create a small-ish 6GB partition and label it something to trigger your memory. I use isos.
format it and copy into it your downloaded .ISO for Mga7, (if you still have it!)
download, and burn to a CD or small USB key, the net-installer for your system: i586 or x86_64.

practice using the net-installer to restore your bootloader, because Windows is likely to offend again.

Caveat: be sure to boot into the same mode, BIOS or UEFI, that you installed in originally.

Boot to the net-installer medium and type "rescue", or if in UEFI mode, choose the rescue option from the menu.
choose to re-install the bootloader from the presented options.
it will ask where to find the installer image and gives a list - network etc. choose Hard disk.
if you have more than 1 HDD, a list of hard disks will be presented, choose the correct disk that has that 6GB partition on it (make a note for future use)
choose your 6Gb partition from the presented partitions.
it will give a list of the contents.

choose your Mga7.iso and follow the prompts.
with practice, you should be up and running after a few minutes.

addendum: the net installer can also be used to install a system from an on-HDD .iso, and it is very fast.

Hi, did you fix it?
Do you have a MBR or a GPT partitioning, is it a BIOS or an UEFI system?
Probably the boot partition or sector was overridden by Windows update, although, I was going through all kind of problems with Windows 10 update, it have never overridden the boot. Especially when it was UEFI-based, because UEFI makes a separation on the boot system for the various systems installed, which is very comfortable for Windows + Linux scenarios. The only problem I've had with Windows 10 updates is that they failed when found Grub and rolled back Windows update entirely. Then I've had to restore/override Windows' boot and then restore Grub after the update was completed, by using doktor5000's method. Do you need more details?

MSW10 updater is utterly buggy.
Here it have not only replaced grub, but also on a triple boot setup (W7, W10, Mageia) it screwed up its own boot loader menu so both the Windows 7 and Windows 10 intems booted windows 10. Sigh. Windows 10 is now eliminated.

morgano wrote: Windows 10 is now eliminated.

This is not a bug, it's a feature

Oh ! In the same time I also meet that problem !
I solved it in another way :
https://www.mageialinux-online.org/foru ... ows-10.php

If I'm not wrong, the windows update add a new partition (what for ? I don't know) and it shift all the partitioning number. Grub is not updated by windows (of course) and does not find the root partition (where the second stage of the bootloader is stored (/boot)).

When grub started, it shown :

Code: Select all

Grub rescue : unknown file system
stem.
grub rescue >

We can list the partitions with ls, for example :

Code: Select all

grub rescue >ls
(hd0,gpt1) (hd0,gpt2) (hd0,gpt3) (hd0,gpt4)

We have to find the root partition of Mageia, recursively, we probe all partition (here called gptX), also with ls :

Code: Select all

ls (hd0,gpt1)/
unknown file system
ls (hd0,gpt2)/
unknown file system
ls (hd0,gpt3)/
boot/ dev/ etc/ home/ lost+found/ media/ mnt/ opt/ proc/ root/ run/ srv/ sys/ tmp/ usr/ var/

On this example, the root partition (which contains /boot) is on gpt3. We have to set it for Grub manually : (Here, all gpt3 occurrences must match the previous partition found)

Code: Select all

set root=(hd0,gpt3)
set prefix=(hd0,gpt3)/boot/grub2
insmod normal
normal

Normally it boots now !
But all this changes are ONLY temporary. If someone reset the computer, all this commands shoud be do again.

In order to fix definitively the bootloader grub :
Start the MCC
Go on the tab "boot"
and clic on "Set up boot system"
clic on "Next"
clic on "Next" again
and finally "OK".