I’ve been using NixOS with a dual boot setup for Windows 11, with each OS installed on its own drive. To switch between them, I’ve been using the BIOS boot priority.
However, last week I reverted to Arch Linux with GRUB (EFI), and now Windows has disappeared from the BIOS. I tried running sudo os-prober, but nothing was detected. I also uncommented GRUB_DISABLE_OS_PROBER=false in /etc/default/grub and reran sudo grub-mkconfig -o /boot/grub/grub.cfg (with the Windows partition mounted), which output the following:
Warning: os-prober will be executed to detect other bootable partitions.
Its output will be used to detect bootable binaries on them and create new boot entries.
However, nothing has worked, and Windows is still not appearing in the GRUB menu.
Here’s the output of sudo fdisk -l:
Disk /dev/sdb: 111.79 GiB, 120034123776 bytes, 234441648 sectors
Disk model: XrayDisk 120GB
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: D21C97E4-1AAF-42B6-8273-48C5F5569216
Device Start End Sectors Size Type
/dev/sdb1 2048 34815 32768 16M Microsoft reserved
/dev/sdb2 34816 234440703 234405888 111.8G Microsoft basic data
Disk /dev/nvme0n1: 476.94 GiB, 512110190592 bytes, 1000215216 sectors
Disk model: WALRAM 512G
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: ADBDC778-9E86-475D-A315-CCCA41A224CF
Device Start End Sectors Size Type
/dev/nvme0n1p1 2048 2099199 2097152 1G EFI System
/dev/nvme0n1p2 2099200 316671999 314572800 150G Linux filesystem
/dev/nvme0n1p3 316672000 1000214527 683542528 325.9G Linux filesystem
/dev/sdb2 is my Windows partition, and /dev/nvme0n1* contains my Arch Linux partitions.