How do I keep GRUB when Windows updates overwrite it on a dual-boot?

[Ella.J]

I’ve been trying to set up a dual-boot system with Windows 11 and Ubuntu on my new laptop, but the Windows bootloader keeps taking over every time. I followed a guide to use GRUB as the main boot manager, but after a Windows update it just disappears and I’m stuck booting straight into Windows again. I’m not sure if I’m missing a step in the UEFI settings or if there’s a better way to handle this so both systems are reliably accessible.

[Joseph_H]

Had a similar setup once. After a Windows update the ESP kept defaulting to Windows Boot Manager and GRUB vanished. I booted from a Live USB, ran grub-install to the EFI System Partition and sudo update-grub, then used efibootmgr -v to move the entry above Windows Boot Manager. It worked for a while, but another update rewrote the boot order again.

[Matthew15]

My take is the firmware is king here. I tried turning off Secure Boot, setting the system to pure UEFI, and ordering the Linux loader first. Windows kept poking at the ESP later on, but at least I could see Ubuntu again when I picked it from the EFI menu.

[Joseph23]

I also turned off Fast Startup in Windows and that seemed to stop Windows from locking the ESP after some updates, but not every time. It’s maddening when you think you fixed it and then it flips.

[Benjamin.G]

One more thought — the problem might not be the bootloader at all. Do you happen to see the Windows Boot Manager listed as the first in the EFI boot order after the update?