Solution:
When I formatted all my drives to install Linux on one and Windows on the other, I kept both connected and they share EFI boot partition as a result. Every time I reinstall Linux it formats the drive and therefore deletes the Windows's EFI Boot as well. One way is to fix this is to reinstall Windows while disconnecting the drive you have Linux on. Or you can move the boot files if you don't want to do that.
I used this guide:
forums.tomshardware.com/thread…
OP:
Currently dual booting as I need Windows for a few tasks and ganes Linux just won’t do. Since setting everything up I’ve reinstalled Linux twice, both times I’ve lost the ability to boot into windows and have needed to reinstall it.
Disk doesn’t show at all in Grub, tried all kinds of things but it just doesn’t show as a bootable OS. It doesn’t show in the boot options in the BIOS or the boot menu for my motherboard. Drive shows up and all the files are still on it. So my guess is the Windows bootloader somehow installs on the same disk that I have Linux on.
I run Linux(Fedora) and Windows on two separate drives.
Windows take forever to install. Anything I can do now to prevent this from happening if I need to reinstall Linux or if I wanna to some distro hopping?
Just to be clear, everything is working right now. But I want to prevent having to reinstall Windows every time I change distro or reinstall my Linux OS
I've recently installed Windows 10 on my new m.2 but when I unplugged my old HDD to perform an easier format on a different HDD, I only reached BIOS as the m.2 does have the OS on it but not the...Tom's Hardware Forum
Yes that’s present and working.
Issue is that my BIOS doesn’t find it either. So something happens when I install a linux distro that breaks the Windows boot loader.
When I reinstall Windows, I can update the grub and it shows up. (It’s also back in the BIOS after reinstalling)
I was hoping to avoid that, but that’s gonna be my next move.
Unless I forget and break windows again.
Words can’t describe how tired I am of choosing the 37 different options during the install, updating the OS 4 times and installing my apps and deleting bloat. 😂
Windows 11 is great and all, but Microsoft loves to make it unbearable to use.
I've had Windows and Linux installed on the SAME drive for decades and don't have this issue. Install Windows first because it WILL fuck up the EFI boot partition, that's inevitable because Windows sucks, then install Linux, use the manual partition option and simply select the existing EFI System partition for the EFI and DO NOT mark format, Linux will then install and leave the Windows boot loader in the EFI partition undisturbed.
Linux WILL overwrite the boot block to start grub instead of the Windows boot loader, but most Linux distros will automatically add a chain boot loader entry to the grub menu to allow you to boot Windows, at least Debian and Redhat derived distros will do this, probably a more manual process in Arch derived distros.
If it does become necessary to install Whendoze after Linux, you can use boot-repair to automatically fix the EFI System partition Windows fucked up or you can boot off of a flash drive, and fix it manually.
First of all: You don't have to reinstall Windows to get it's bootmgr EFI and supporting files back into the ESP. Installing those from the CLI in from a booted install media is possible, I did it before. You can even install all of Windows manually if you ever need to, it's just annoying to do with the windows command line tools.
Secondly: I'm not familiar with all distro installers, but surely you can just not format the ESP? Worst case scenario you'd have to use manual disk formatting I guess, but it's not that difficult.
Thirdly: You said Grub doesn't show the disk. If you mean the Grub command interface didn't show the disk, then the issue is deeper, at a UEFI or hardware level. If you mean there are no boot entries for a Windows install to be selected, then it could be that they were not generated because the Windows bootmgr EFI was not found when Grub got installed. Sometimes just booting back into Linux and running os-prober again might be enough, if the Windows bootmgr EFI is still around. On my distro the os-proper is automatically run when I run grub-mkconfig -o /boot/grub/grub.cfg
I've always used a shared ESP for my dual boot systems and I certainly don't reinstall one OS as the result of a change with the other.
Yeah, I have to do that after reinstalling Windows again. Just did and that solves the issue of getting it into Grub so that I wont have tot go through the BIOS.
But when I install Linux, the Windows boot disappears from the BIOS too. Even tried to find it trough the «Repair» options when booting from a Windows USB, but it’s just gone.
Is it possible that Windows and Linux shares UEFI partitions even if they’re on different drives?