Free up some space on your disk for Windows. Leave it unformatted/unallocated.
Remove the esp and boot flag from EnOS’ EFI System Pertition.
Launch Windows’ installer and point it to that unallocated space. Install Windows.
Backup your valuable files from your EnOS. Any disk manipulation, installation etc. might carry a certain risk, however little. Better to be on the safe side.
I have installed in the same way as described above but it was quite a long ago. Back then it worked fine for me. I can’t speak to Windows 11 and if there has been any changes to the way its installer work now.
If you have more than one disk so perhaps you could use the other one.
If not then yes, you would need to shrink your current system partition to make space for Windows.
Don’t create a partition. Leave the space unallocated.
At any rate, I would remove the above mentioned flags from EnOS’ ESP. Windows’ installer tends to look for a partition flagged as esp and if it finds one, it will use it as the location for its boot files, instead of creating a separate one. It shouldn’t overwrite what is already in there but there is a tiny risk. There have been “reported” cases, so you never know.
Install Windows into that 128.52 Gio, non alloué space.
It should create its own ESP and put its bootloader in there.
In the case that it still uses the currently existent ESP and also overwrites its content, make sure to have an EnOS live usb handy so we can install Grub again from the live session using arch-chroot.
Thank you. So I just installed Windows 10, and after a few reboots (Windows asked to reboot a few times), Windows is up and running.
I haven’t tried yet to boot EndeavourOS, but I assume it is still working. I imagine I just have to select EndeavourOS in the boot sequence and put it up/first in the boot sequence (as I do when I want to boot from a usb key using Ventoy)…
Now Windows doesn’t recognize my NVIDIA GPUs but I imagine I have to go to a Windows forum to ask for help…
Still one more thing, do I have to re-check boot and esp?
Yes, I would like to do so. How could I do that please? Can it cause problems later? When updating one of the OS? I am using snapper-support btrfs-assistant for snapshots, snapshots that do appear on the Grub.
As for Windows, now my NVIDIA drivers are recognized. I could install Davinci Resolve and it’s working fine (that’s the reason for me to dual boot with Windows, as I was unsuccessfully fighting to use Resolve on EndeavourOS, NVIDIA drivers causing difficulties).