Hi all, really appreciate all the quick replies. I’ve managed to resolve it, It turned out to be some kind of obscure bootloader bug on Acer machines caused by SecureBoot.
To anyone else facing the same issue, here’s how I solved it without any re-installation:
- Login to Windows
- Mount the EFI partition (ESP) and access it using an elevated explorer (like Explorer++)
- Take a backup of the EndeavourOS (or your distro) directory inside the EFI directory, and then remove it from that partition
- Reboot now, and you should be able to access your BIOS
- Turn on SecureBoot from the BIOS and reboot into Windows again
- Do step 2 again, and this time put the EndeavourOS directory back in the EFI directory
- Reboot now, enter the BIOS, and turn on SecureBoot
- In the security settings, you have the option to “Select a UEFI file as Trusted”, choose that and select the .efi file inside your EndeavourOS directory (that you put in the EFI partition)
- Save, reboot, and enter the BIOS again
- You should now be able to see EndeavourOS in the Boot Order section, change the priority to put it at the top
- Done - you should ideally be able to access the Grub menu, and also the BIOS perfectly now.
- (Optional) Turn off SecureBoot - In my case, I was not able to access EndeavourOS even after adding it to the Trusted UEFI files list, so I had to turn SecureBoot off to boot into the Grub menu. But now I’m still able to access the BIOS as well.