Update 2: Finally did it by following the first option I explained in my own comment (i.e. backup and reinstall)

Update 1: I also updated the UEFI just to be sure and the issue persists as expected

Sorry if the post is long, trying to give each relevant detail.

My system has two drives, the first for Linux and the second for Windows.
Initially I had OpenSUSE MicroOS on the first and I could boot into Windows through the UEFI, but then I installed Fedora on it and lost the ability to get into Windows since. I thought that it had a boot partition on its own drive, but I guess I was wrong since now that I checked the partitions, there is no FAT32 partition on there.

image of partitioning scheme for Windows drive

(in text form)

nvme0n1                                       931,5G disk              
├─nvme0n1p1                                      16M part              
├─nvme0n1p2                                   930,8G part  BitLocker   
│ └─bitlk-66306                               930,8G crypt ntfs
└─nvme0n1p3                                     692M part  ntfs

Unlike on my Linux drive image of partitioning scheme for Linux drive

(in text form)

nvme1n1                                       931,5G disk              
├─nvme1n1p1                                     600M part  vfat        /boot/efi
├─nvme1n1p2                                       1G part  ext4        /boot
└─nvme1n1p3                                   929,9G part  crypto_LUKS 
  └─luks-353e522f-c0f3-4167-99fc-90d576a734e8 929,9G crypt btrfs       /var/home

So I probably destroyed the content of the boot files in its installation process.

I’m able to access my BitLocker encrypted drive through Fedora, so if I have to reinstall I can still make a backup (it wasn’t very important to me either way).
I also fired up a Windows recovery drive to see if it detected the system and it does, I haven’t yet looked at what the recovery drive can do, so if that’s the key to solving this let me know.

The actual question

So at this point I wonder: is there a way to restore the Windows boot option? Would I have to do it in some GRUB config or do I have to/can I create a boot partition on the Windows drive too and somehow write the bootloader there?

  • @[email protected]English
    5•1 year ago

    If I’m understanding you correctly, you were on the right track. Use the windows recovery disk to recreate the windows bootloader. It SHOULDN’T touch your Linux drive in the process, but I would remove it just to be sure as Windows always assumes it’s the only OS present. From there I believe you could create a GRUB entry for the windows bootloader and then use GRUB to control which you boot from. I haven’t done any GRUB configuration in a very long time, so you will need to Google that one, or maybe someone else here can chime in on how to get that working.

    • @QuazarOmegaOPEnglish
      1•1 year ago

      Thanks for the input! I had a suspicion too with Windows being potentially aggressive with the drives so my first thought was to take out the other drive too, I’ll try to go that way then.

      Do you have any links to the process needed to restore the bootloader with the recovery tool?