Troubleshooting Reboot Issue in Windows 11

#microsoft #reboot #deadlock #ubuntu

Written: December 04, 2025

Issue

In my laptop, Windows 11 has an issue with rebooting. Each time it tries to reboot, I immediately run into a system hang, with blank screen and unresponsive keyboard.

However, rebooting works perfectly fine within Ubuntu. Thus, I wanted to set Ubuntu as First preference instead of Windows.

Setting Ubuntu as First Preference

I went to boot manager and changed preference order

anu@laptop:~$ sudo efibootmgr
[sudo] password for anu: 
BootCurrent: 0001
Timeout: 0 seconds
BootOrder: 0004,0001,0003,9999
Boot0004* Windows Boot Manager.........
Boot0001* Ubuntu........
Boot0003* Solid State Disk........
Boot9999* USB Drive (UEFI)............

anu@laptop:~ sudo efibootmgr 0001,0004,0003,9999

Attempts

Turning off Fast Startup
Setting Windows as the default option in Ubuntu GRUB
Giving Windows first preference in Startup

Result: It didn't work.

Current Status

Thus, I have postponed this issue until I have time to work on it again. And I set Ubuntu as the first preference in BIOS, so it will automatically prefer Ubuntu.

Steps Taken:

Edit Grub: sudo nano /etc/default/grub
Set: GRUB_DEFAULT = 0
Update & Reboot:

sudo update-grub sudo reboot

Update:
I realized that the same issue pops up if I boot using Windows even once. It seems that the boot order is overwritten by windows.. so I have to fix it each time I log in to Windows..