Re-installing Windows 10 after Manjaro

Hi,

My computer came with a rather bloated Windows 10. I installed Manjaro in a dual boot after a while and it works just fine with dual boot and everything. I am now thinking of re-installing Windows 10 to get a clean installation. Will this overwrite the Grub so I have to fix the Grub in the same way as if I had simply installed Manjaro first and then Windows afterwards? Or will the presence of an existing Windows installation mean that the Grub somehow stays put?

if you are going to completely erase the disk and install only windows then you don’t have to worry about grub

Hi @gecko8k, and welcome!

In my experience Windows tends to take over everything. It might’ve changed since I last dual-booted with it, but that’s my experience.

The last time I did it, I didn’t know how to fix grub on its own, without reinstalling Linux after Windows was installed. That was a long, long, long time ago, though.

I believe it would be sufficient once you’ve reinstalled Windows, to just reinstall, or update grub again. Although now that I think about it, to do that I guess you’d have to boot with a live ISO and enter a chroot environment. It probably depends on your setup.

Hope this helps!

Yes, you’ll only have to worry about grub if you’re going to continue to use dual boot.

Windows installer can detect the presence of existing EFS partition, so just ensure you tell it right where it is, it will only register its bootloader there, not overwriting the partition. I did not do any bootloader fix after reinstalling Windows (my laptop came with Windows, I then overwrite everything with Manjaro, but then have a need for Windows 10 to help office colleagues who are still using it). I use rEFInd instead of GRUB as my boot manager, though. But essentially as long as it’s EFI, doesn’t matter what boot manager you’re using, assuming it’s implemented correctly.

Thanks all three for your answers. I think I will go ahead and try re-installing Windows 10 in a dual-boot and see what happens. If the Grub disappears I will live-boot into Manjaro and update the Grub through chroot.

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