[Solved] Master Boot Record UEFI Booting?

Software & Operating Systems
1

Just wondering if Master Boot Record formatted OS drives can UEFI boot, or if UEFI booting is specific/only allowed for GUID drives.

2

It’s possible and I don’t even believe it after doing it myself. None the less, I’ve never seen an OS install support both Legacy and UEFI at the same time.

I found a video and decided to try it myself because I wasn’t sure if it would work on the bare metal side of things, but it did. Source: https://www.youtube.com/watch?v=9gWKNIz4C-o

Unfortunately didn’t have luck with Windows 7.

It’s someone with a heavy Indian accent, so I’ll just put the instructions here for those interested.

  1. Install Windows
  2. Mark the C drive partition as active in Disk Management
  3. Run Command Prompt as admin
  4. Type: “bcdboot C:\Windows /s C:”
  5. Restart system
  6. Open Disk Management
  7. Format the system reserved partition as FAT32
  8. Give the partition a new name as well
  9. Change the drive letter to D
  10. Run Command Prompt as admin
  11. Type: “bcdboot”
  12. Type: “bcdboot C:\Windows /s D: /f ALL”
  13. Go back to Disk Management and set the system reserved partition
    as active
  14. Restart the system and you should see a UEFI/Windows Boot Manager option in the BIOS
3

Anyone know if it’s possible for Linux and/or OS X/macOS?

4

Don’t do it. But here you go.
https://wiki.archlinux.org/index.php/Systemd-boot#BIOS_boot

You can also use Duet to help with this but I don’t think that is being maintained anymore.

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