Can no longer boot into Kubuntu

[jim204]

Hi,

I recently tried to do an upgrade from v22.04 LTS to the latest version by following the below steps. (There might be another step missing as I asked chatgpt for the process, and I can't find that history.)

sudo apt update && sudo apt upgrade -y
sudo apt install update-manager-core


Anyway, after doing so, before doing the actual upgrade, I was asked to reboot. Upon rebooting, the grub boot loader stopped showing up. (I have two operating systems, Windows 10 and Linux which are installed on different physical drives. The screen would just go black, and it would reboot into bios.

Next I tuned the computer on, this time I manually pressed (F12), to choose the boot sequence, and I chose the windows 10 boot manager drive. When trying to boot into windows I got the bitlocker encryption message, saying some hardware/system settings have changed, prompting me to enter my recovery key. In doing so, I can boot into windows, but still not kubuntu and my grub bootloader is gone.

I am not sure if the bitlocker drive encryption is source of the reason kubuntu will no longer boot, or its a coincidence in timing, and the reason is down to me trying to update.

So in summary,

- Tried to update Kubuntu
- Rebooted and am no longer able to boot into kubuntu (I just get a black screen and it reboots back into bios)
- Have fixed the bitlocker encryption and have now turned it off (so the drive is no decrypted).

Any ideas on where I should start in trying to solve this problem?

Let me know if there is any details I have missed in helping me out with this issue.

[spiderman]

I read a similar post where a user had an AUS that after a MS update to windows, they filled up the NVRAM so no other systems would boot except windows. This user had to go into the bios and open up secure boot, then edit OR clear out all the boot entries in the bios secure boot section. All bios is different, but they may have similar layouts. Secure boot is not needed for Ubuntu or WINXXX), but if that gets filled up for some reason (because you are dual boot) you may have these types of issues. What are the details of your machine/bios? Refered to issue here: https://www.kubuntuforums.net/forum/...23-04-10-24-04

[jim204]

Thanks for you reply.

Regarding the secure boot, I have looked everywhere in bios and I can't find this secure boot option, or any mention of keys. My motherboard is Gigabyte x570 Gaming X running the F35 version.

Since making this post, I have created a live Kubuntu usb which I can boot into, and have access to a terminal. I tried to reinstall grub, but when doing so, I got a message saying "EFI variables cannot be set on this system". Hope this helps, please advise any other suggestions

[Qqmike]

I am no longer familiar with Windows nuances, especially with booting issues.
However ... it sure sounds to me that you do not have an EFI/UEFI system.
It sounds like you have a legacy (older) GRUB system (and regular BIOS on your computer).
In any case ... a good thing to do (while waiting on perfect clarity) would be to use Boot Repair.
See here:
https://help.ubuntu.com/community/Boot-Repair
It has it's plusses and minuses, but overall it could easily shed some light on what's going on.
(You can also try some things from your live Kubuntu USB, but that can get messy or more advanced/tricky.)

[spiderman]

Also, I used a boot repair disk I got from source forge dot net... ( https://sourceforge.net/projects/boot-repair-cd/ ) and it did a great job for me. Let us know how it goes. QQ is right, sounds like the legacy boot and UEFI boot got mixed up.