[SOLVED] problem with dual boot ubuntu/w10 at GRUB: cannot load image

[pfelelep]

You have two disks on your PC, would you consider Windows on one disk and Ubuntu on the other?

Actually, if you would be kind to help me through the steps, I'll be happy to try

I reckon we could eliminate the haunting before Halloween

Hehe, you have a plan Dr Venkman?

[tea for one]

Actually, if you would be kind to help me through the steps, I'll be happy to try
Hehe, you have a plan Dr Venkman?

Yes, I have a plan
Let’s see if it is suitable for you?

The plan is to tidy up the Windows disk sda and install Ubuntu on sdb

Backup all personal data from disk sda (both Windows and Ubuntu)
Backup data from disk sdb because you will eventually install Ubuntu here

Power off and remove disk sdb
Leave Windows on disk sda attached
Reset UEFI settings to default

Boot Windows and use Windows tools to remove Ubuntu partition from sda
(or boot live Ubuntu session and remove all Ubuntu partitions from sda)
Possibly remove duplicated Windows recovery partition
Boot into Windows and check data is intact
Run chkdsk and other utilities to double check
Reboot a couple of times (just checking and re-checking)
Happy that Windows is booting and functioning as normal?

Remove Windows disk sda
Attach disk sdb
Disable Secure Boot and any TPM settings in UEFI
Boot into live Ubuntu 24.04 session in UEFI mode
Open Gparted and create GPT (this will completely remove all data and partitions, it doesn’t matter because you have a data backup)
Install Ubuntu 24.04 (your disk is approx 2TB so you may wish to leave free space for a shared NTFS partition later and/or other partitions)
Suggestion:-
ESP = partition 1 (default 1.13GB)
System = partition 2 say 50GB – Choose Ext4
Home = partition 3 say 100GB – Choose Ext4
Restore Ubuntu data
Reboot a few times to check that everything is OK
Add shared partition(s) later when all tests are satisfactory

The objective is:-
Windows and Ubuntu boot and operate independently
Each OS has its own ESP
If one fails to boot, it doesn’t affect the other (i.e. boot via PC boot menu)
A shared NTFS data partition can be added if required
Windows tools to repair Windows and Ubuntu tools to repair Ubuntu
For convenience, we can make grub boot Windows if you wish (although Windows will always boot independently)

[pfelelep]

Hello, sorry for the late reply, I have been busy with some family matters.

@tea for one
Thank you so much for the detailed instructions, I will definitely work on it, but I need to get an external hard drive to backup the ssd first.

At the moment, I am investigating on a possible grub2 issue related to the latest 24.10 ubuntu, as seen on the askubuntu forum:

It's due to an issue in GRUB2 being non-compatible with non-NX shim which includes Windows 10 https://bugs.launchpad.net/ubuntu/+s...2/+bug/2084104

[pfelelep]

Greetings everyone,
sorry for the VERY late update, but the problem has been solved with an GRUB2 update, as the solution posted on the askubuntu forum:
https://askubuntu.com/questions/1530...-kubuntu-24-10

answered Oct 16 at 19:42



bushkov:

It's due to an issue in GRUB2 being non-compatible with non-NX shim which includes Windows 10

answered Nov 15 at 15:38



Milanium

Follow the instructions at https://wiki.ubuntu.com/Testing/EnableProposed then in a console sudo apt install -t oracular-proposed grub-common grub-efi-amd64-bin grub-efi-amd64-signed grub-efi-amd64-unsigned grub-pc grub-pc-bin grub2-common

The grub dual boot allows to boot from windows normally (/phew/).

MY deepest thanks to everyone who helped me as I was really "circonvolutionning" madly.

I would like to thank personally ubfan1, yancek, oldfred and especially tea for one, who patiently wrote me a very detailed step-by-step method to make a clean reinstall of both ubuntu and windows on 2 separate HDs (I hope to use this method after new year, when my 2 daughters leave me some time to focuse on the task )

problem solved, I will update the title of that post, I hope it can help other people.