I tried adding grubx64.efi in the Windows Boot Manager using BCDEdit. However when I boot up my computer and try to start GRUB from Windows Boot Manager by clicking on the entry I created, I get:
File: \EFI\ubuntu\grubx64.efi
Status: 0xc000007b
Info: The application or operating system couldn't be loaded because a required file is missing or contains errors.
I know that the efi file works because I can boot GRUB up, from the same file, from the same location (the ESP partition) using an EFI shell, such as the one found in this answer: https://unix.stackexchange.com/a/63898/167564
Here's my bcdedit output:
Windows Boot Manager
--------------------
identifier {bootmgr}
device partition=\Device\HarddiskVolume2
path \EFI\Microsoft\Boot\bootmgfw.efi
description Windows Boot Manager
locale en-US
inherit {globalsettings}
flightsigning Yes
default {current}
resumeobject {4c60dca4-e732-11e5-be25-b3798e2bd780}
displayorder {current}
{4c60dcaf-e732-11e5-be25-b3798e2bd780}
toolsdisplayorder {memdiag}
timeout 10
Windows Boot Loader
-------------------
identifier {current}
device partition=C:
path \WINDOWS\system32\winload.efi
description Windows 10
locale en-US
inherit {bootloadersettings}
recoverysequence {4c60dca6-e732-11e5-be25-b3798e2bd780}
recoveryenabled Yes
isolatedcontext Yes
flightsigning Yes
allowedinmemorysettings 0x15000075
osdevice partition=C:
systemroot \WINDOWS
resumeobject {4c60dca4-e732-11e5-be25-b3798e2bd780}
nx OptIn
bootmenupolicy Standard
Real-mode Boot Sector
---------------------
identifier {4c60dcaf-e732-11e5-be25-b3798e2bd780}
device partition=\Device\HarddiskVolume2
path \EFI\ubuntu\grubx64.efi
description Grub Test
locale en-US
inherit {globalsettings}
flightsigning Yes
custom:23000003 {current}
custom:23000006 {4c60dca4-e732-11e5-be25-b3798e2bd780}
custom:24000001 {current}
{4c60dca8-e732-11e5-be25-b3798e2bd780}
custom:24000010 {memdiag}
custom:25000004 10
As you can see by the output, the last entry was the one I experimented trying to get Grub to work, the one that says "Real-mode Boot Sector". I created it by creating a copy of "{bootmgr}", and renaming it to "Grub Test", and changing the path to where grub was located. I saw this answer, and it says the correct entry is bootsector, so I went into regedit and changed it from "Windows Boot Manager" to "Real-mode Boot Sector", by changing values under BCD00000000 as explained in this post: Windows 8.1 UEFI x64 is not able to boot-up UEFI Images
I also tried changing it to:
0x10100003(Firmware Application)0x10100002(Windows Boot Manager)0x10200003(Windows Boot Loader)0x10400008(Real-mode Boot Sector)0x20200008(Inherited Settings)
However they all ended up with:
File: \EFI\ubuntu\grubx64.efi
Status: 0xc000007b
Info: The application or operating system couldn't be loaded because a required file is missing or contains errors.
Can I somehow make Windows Boot Manager be able to boot Grub? I searched all over the Internet and couldn't find anything of use to me, I'm kind of frustrated.
Also, secure boot is turned off.
