I had multiple disks in my PC, one with Windows and one with Linux. The drive with Linux had the boot record I guess; I removed and replaced that one with a new disk and again installed Linux on it (so the Windows disk has been the same the while time), but I can no longer log into Windows while this new disk is installed and the old disk is removed. I can log into Linux while the new disk is installed, and if I swap back to the old disk I can log into Windows.

How do I fix things so I can not into Windows or new Linux while the new disk is installed? I don’t mind reinstalling my Linux OS, but I really don’t want to reinstall Windows.

  • Skull giver@popplesburger.hilciferous.nlEnglish
    5·
    1 year ago

    It’s possible Windows installed its bootloader and boot partition onto the drive you removed.

    Assuming the rest of your system is on the drive you didn’t swap out, you can try copying the Windows boot sector byte for byte from the swapped out disk to a partition on the new disk. Make sure to also set the necessary partition flags. Then you can probably boot a Windows installer and use the common boot fixes (fixboot.exe and friends).

    Assuming you have a modern Windows system, you also need to make sure the UEFI partition (a FAT32 partition that contains a file path something like /EFI/grub/grubx64.efi) also contains the Windows bootloader.

    On a single disk you would end up with something like this:

    Disk name Partition 1 Partition 2 Partition 3
    /dev/disk/by-diskseq/1 UEFI (a few GB, FAT32) Windows partition (hundreds of GBs) Windows boot partition (±300MB)
    /dev/disk/by-diskseq/2 Linux boot partition (1-2GB) Linux swap partition (same size as your RAM) Linux partition (hundreds of GBs)

    Your Linux layout will depend on your settings. If you use LVM, all partitions are probably virtual partitions within one large partition. One or more may be wrapped inside an encrypted partition as well.