Qubes and Windows dual boot

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1

I’m new to Qubes. I installed it on a computer that has Windows, planning to keep the two OS, not because I like Windows, but because of paperwork I have to do from time to time and because I have to write on certain apps for college.

But Grub is not showing me Windows. It simply gives me the options of going to Qubes, Advanced booting on Qubes, and UEFI Firmware Settings. So, if I need Windows, I have to get into the latter, change the order of booting for the OSs and then I can work in Windows.

I’ve tried many things for long hours for three days now, including entering different commands on dom0, and the GNU nano to add entries manually to Grub, like here Multibooting | Qubes OS

Other solutions assume that my computer can go back to Legacy mode, and that’s not the case, it only works with UEFI (A Lenovo I bought 3 months ago). So, certain apps that should fix the problem don’t work, like EasyBCD, saying that it’s due to restrictions imposed by Windows.

Finally, is it true that Windows could compromise Qubes security in my case?

Any ideas would be appreciated. Thanks for reading.

2

Hi @anon79337522, welcome to the forum!

YES. Very much so. Until I can take the entire Windows codebase, compile it myself, and get the exact same end result as the binaries Microsoft ships, I will always treat it as suspicious (and you really should too).

The only thing stopping Qubes OS from not being treated like any other regular files that anyone can touch, is Qubes OS booting as the operating system and actively denying other programs access.

If Qubes OS isn’t the one “calling the shots” on your machine, well, then your Qubes OS installation is at the mercy of whoever is calling the shots.

Read, write, delete, alter, overwrite, purge, hardware firmware, everything. Qubes OS doesn’t get a say in any of those if it’s not booted as the operating system. :slight_smile:

Even simply booting the Windows Installer ISO has been known to completely obliterate any UEFI entries and GRUB partitions, simply because Microsoft…

If I may:

Is there anything stopping you from running Windows inside a Qubes HVM?

Unless you are doing some heavy gaming, or anything that checks whether you’re inside a VM or not, then it’s highly likely that you’d be able to fulfill all your Windows needs with a Qubes HVM, and it’s definitely worth considering.

Yes, Qubes OS doesn’t come with the os-prober package installed in dom0.

If you really want, you can install it with:

sudo qubes-dom0-update os-prober

That, unfortunately, is quite old (it was written when Qubes version 3 was in its prime), and needs to be updated a little :sweat_smile:

Windows 11, particularly the more recent builds, have come out of left-field and broken quite a lot of things in the dual-booting scene…

I strongly discourage you from paying anyone for a bootloader (especially when you’ve never met them, nor necessarily trust them :stuck_out_tongue:), or at the very least, I discourage you from using one whose codebase you cannot audit.

GRUB should be sufficient for your needs :slight_smile:

os-prober should work. Let us know if you need any help :slight_smile:

3

Thanks a lot. Actually, after doing my research I deleted Windows and I’m going to keep Qubes OS only. I’m going to use what I need from Windows in HVM. I just don’t know how to start yet. Could you please help me?

4

This would be a good place to start:

You can even convert your existing Windows installation into an HVM.