I cant boot into Ubuntu

Question

I recently dual-booted Ubuntu and i can't boot into it.

My first time doing this there were no problems. But now there are and i dont know how to fix it. Here are the errors that appear after trying to boot.

error: /boot/vmlinuz-5.4.0-45 has invalid signature

error: you need to load the kernel first.

If you need more information let me know because i dont know what information to give in this situation. Thanks!

Do you get some sort of a prompt, i.e. can you enter commands, like in this answer? — Jos, Sep 01 '20 at 13:12
I was greeted with the error message and after a few seconds it dissapeared. Now im trying to reinstall Ubuntu — Tresquel, Sep 01 '20 at 13:14
Did Windows do an update to UEFI and turn UEFI Secure Boot on? — oldfred, Sep 01 '20 at 13:51
@Jos tried to do that things in the answer but the errors are the same — Tresquel, Sep 01 '20 at 14:17

score 2 · Accepted Answer · answered Sep 01 '20 at 17:16

2

Disabling Secure Boot solved the problem.

answered Sep 01 '20 at 17:16

Tresquel

21

but that is not best solution although can startup... – Rγσ ξηg Lιαη Ημ 雷欧 Jan 05 '22 at 16:59

Hani Shams · Answer 2 · 2022-01-17T12:33:48.550

For those people who may not want to disable Secure Boot permanently

In my case reinstalling shim-signed solved the problem.

First, temporarily disable Secure Boot from the BIOS, then reinstall shim-signed:

sudo apt purge shim-signed
sudo apt install shim-signed

Then re-enable Secure Boot in the BIOS.

Make sure Secure Boot is enabled:

sudo mokutil --sb-state

Also if you have a third-party driver(e.g. Nvidia) you should reinstall the driver and then, a pop-up window will be displayed asking for a password for enrolling key on the next reboot:

Then reboot the system and immediately after reboot you will see something like this:

Select Enroll MOK and then enter the password that you set before.

I cant boot into Ubuntu

2 Answers2