Re: Advise on how to debug screen with only GRUB and blinking cursor and possibly save my dualboot installation

[Pascal Hambourg]

Le 19/12/2022 à 15:20, Sophoklis Goumas a écrit :
> This kind of confirms the output of the boot-repair-disk which I've only used
> for debugging the situation, namely:
>
> > Grub2 (v1.99-2.00) is installed in the MBR of /dev/sda and looks
> > at sector 2048 of the same hard drive for core.img, but core.img
> > can not be found at this location.

Can you post the full report from the current state, excuding the 
grub.cfg part ? After you ran grub-install, the core image should be 
present again in sda1. But /boot should now be gone.

> I haven't used any of that disk's/utility's "repair" options so that
> the system will not get messed up any further and I'd like to retain it's
> current status for the reason I explain further down.

If you ran grub-install on /dev/sda, it messed up the system.

> > This is wrong. A BIOS boot partition (bios_grub flag) should not contain
> > a filesystem. The purpose of this type of partition is exclusively to
> > store a raw GRUB core image.
>
> This setup, as unconventional/wrong as it is, WAS working flawlessly
> for more than 4-5 years

Such setup cannot possibly work and is doomed to break. The same 
partition cannot be used as bios_grub and /boot at the same time. Also, 
I fail to see how Windows could be the culprit unless it messed with the 
partition table itself and merged the two partitions.