For me it was migrating my Arch install from EXT4 to ZFS. GRUB had to be configured in particular ways to get it to work with ZFS and I didn’t do it properly so it wouldn’t/couldn’t boot.
Then I updated ZFS to a version that wasn’t supported by GRUB yet so I chrooted into my installation to switch to Systemd-boot with Unified Kernel Images. Now I still can’t figure out how to add a boot entry for Windows. I followed the proper steps I think but selecting the Windows entry just reloads Systemd-boot.
For me it was migrating my Arch install from EXT4 to ZFS. GRUB had to be configured in particular ways to get it to work with ZFS and I didn’t do it properly so it wouldn’t/couldn’t boot.
Then I updated ZFS to a version that wasn’t supported by GRUB yet so I chrooted into my installation to switch to Systemd-boot with Unified Kernel Images. Now I still can’t figure out how to add a boot entry for Windows. I followed the proper steps I think but selecting the Windows entry just reloads Systemd-boot.