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@degski OK from your last paste I see this in /boot/efi/EFI/Microsoft/Boot/ for lines 26-28:

-rwx------. 1 root root   18600 Nov 13  2017 bootmgfw.efi
-rwx------. 1 root root 1253792 Aug  7 09:12 bootmgfw__.efi
-rwx------. 1 root root 1257376 Aug  3 06:39 bootmgr.efi

I do not know what the first one is, but 18600 bytes is bogus. The second file has the correct size, but it's incorrectly named. My advice is to remove the first one and rename the second one to bootmgfw.efi. For example on my dual boot Windows 10:

-rwx------. 1 root root 1273760 Aug  2 15:39 bootmgfw.efi
-rwx------. 1 root root 1257376 Aug  2 15:39 bootmgr.efi

I think this explains at least the problem being unable to boot Windows 10. Both GRUB's configuration file, and the Windows boot entry in NVRAM (efibootmgr), are currently pointing to this bogus 18K file that cannot possibly be a valid Windows bootloader. For what it's worth, on any Windows 10 bootable USB stick, if you mount it and look around for bootmgfw.efi you can copy that to your local /boot/efi/EFI/Windows/Boot instead. This file is supposed to be signed by Microsoft! So as long as Secure Boot is enabled, you are protected in case a bootloader file is actually malware. If you disable Secure Boot, the firmware will blindly use unsigned bootloaders! So...if I were being a little paranoid, and wonder what a bootkit attack might look like, it might look like this! Make someone's computer unbootable and see if they disable secure boot and now I'm in! This is why I'm really really fussy about any advice to disable Secure Boot without thoroughly understanding why someone's having the problem they're having.

I'm on #fedora and #fedora-qa right now, if you join either channel and type cmurf I'll get a notification.

@degski OK from your last paste I see this in /boot/efi/EFI/Microsoft/Boot/ for lines 26-28:

-rwx------. 1 root root   18600 Nov 13  2017 bootmgfw.efi
-rwx------. 1 root root 1253792 Aug  7 09:12 bootmgfw__.efi
-rwx------. 1 root root 1257376 Aug  3 06:39 bootmgr.efi

I do not know what the first one is, but 18600 bytes is bogus. The second file has the correct size, but it's incorrectly named. My advice is to remove the first one and rename the second one to bootmgfw.efi. For example on my dual boot Windows 10:

-rwx------. 1 root root 1273760 Aug  2 15:39 bootmgfw.efi
-rwx------. 1 root root 1257376 Aug  2 15:39 bootmgr.efi

I think this explains at least the problem being unable to boot Windows 10. Both GRUB's configuration file, and the Windows boot entry in NVRAM (efibootmgr), are currently pointing to this bogus 18K file that cannot possibly be a valid Windows bootloader. bootloader.

For what it's worth, on any Microsoft supplied Windows 10 bootable USB stick, ISO image, if you mount it and look around for bootmgfw.efi you can copy that it to your local /boot/efi/EFI/Windows/Boot instead. /boot/efi/EFI/Windows/Boot. So if the copy you have still doesn't work after renaming it, get a known good one. You can download Windows 10 install ISOs from Microsoft's web site for free without a serial number. This bootloader file is supposed to be signed by Microsoft! So as long as Microsoft, and that signature is what UEFI Secure Boot is enabled, you are protected in case a being enabled is checking (among other things).

If Secure Boot is disabled, this bootloader file is actually malware. If you disable Secure Boot, the firmware will file's signature is not validated, it's blindly use unsigned bootloaders! used. So...if I were being a little paranoid, and wonder what a bootkit attack might look like, it might look like this! Make someone's computer unbootable and see if they disable secure boot and now I'm in! This is why I'm really really fussy about any advice to disable Secure Boot without thoroughly understanding why someone's having the problem they're having.

I'm on #fedora and #fedora-qa right now, if you join either channel and type cmurf I'll get a notification.