smac89
Posted on December 6, 2021
Introduction
Sometime last week, I decided to move my entire ESP folder into a dedicated boot partition mounted at /boot
. (I did this because I liked the idea of having everything boot-related in a partition for easy access when I dual boot or need any file from there). Unfortunately, I didn't attempt to reboot in order to check if anything was broken...until today
Windows boot is broken...
And by "broken", I mean that in the rEFInd boot menu, there was nothing showing for windows. It only showed my linux installation.
At first, I was sure this was an easy fix and all I had to do was boot from a linux disk image, and run the commands:
mount /dev/sda3 /mnt
mount /dev/sda1 /mnt/boot
refind-install --root /mnt
...unfortunately, that didn't work :(. Attempting to boot directly from Windows Manager
also didn't work, so at this point I knew something had gone very wrong.
As my sunday evening grew into sunday night, I decided to actually stop being lazy with this fix, and discover why windows was being soo elusive.
Steps to recovery
Using the steps outlined in the arch wiki for rEFInd, I was able to get my hands on an EFI shell. Using some of the commands from the arch wiki, I was able to discover that the windows boot EFI file didn't exist anymore in the boot partition.
Well that explains a lot!
Both rEFInd and Windows boot manager expected to find a \EFI\Microsoft\Boot\bootmgfw.efi
file, but it wasn't finding it, so the boot never worked.
Step 1. Add bootmgfw.efi
to rEFInd
Boot into Linux and mount your windows partition, then copy the existing file into where rEFInd was expecting to find it.
sudo mkdir -p /boot/EFI/Microsoft/Boot
sudo cp /run/media/smac89/Windows/Windows/Boot/EFI/bootmgfw.efi /boot/EFI/Microsoft/Boot
At this point, you will see the blue windows logo from the rEFInd boot menu, but attempting to boot from it may result in the following screen:
...if so, continue to the next step
Step 2: Get access to a windows terminal
There are many ways to do this. Pick the one that is most convenient, and proceed.
Inside the terminal type the commands:
diskpart
list volumes
Find the volume containing the boot partition, and assign it a label if it doesn't have one:
select volume N
assign letter=m
Exit diskpart
exit
Finally, we use the following command to install windows boot entries to the boot partition:
bcdboot C:\Windows /l en-US /s m: /f ALL
After running the above command, the boot partition now contains all the entries needed to boot windows.
Reboot.
Thanks for reading.
Posted on December 6, 2021
Join Our Newsletter. No Spam, Only the good stuff.
Sign up to receive the latest update from our blog.