[Windows 10] Guru Meditation error on all Windows machines after Windows update (19042)

[Hidde]

After the latest windows update, I can't boot windows machines on VirtualBox. I'm getting Guru Meditation error: (VINF_EM_TRIPLE_FAULT).
OS: Windows 10 home
Version: 10.0.19042 Build 19042

Code: Select all

00:00:35.134116 !!         VCPU0: Guru Meditation 1155 (VINF_EM_TRIPLE_FAULT)
00:00:35.134139 !!
00:00:35.134143 !! Skipping ring-0 registers and stack, rcErr=VINF_EM_TRIPLE_FAULT

To make sure I checked that VT-x is enabled in Bios. It happens only after the update.
I attached the logs.

[mpack]

After a Windows update?? You still have the Windows 2019 install CD in the drive, you are still booting from the CD. According to the log you are trying to install Windows, so there can never have been any update.

Trying switching to the Windows 2016 template.

[Hidde]

I meant an update on my main windows machine, not on the Virtual Machines. I attached the logs for windows I tried to install but the error was the same for all Windows Virtual Machines. This isn't the case with Linux machines that works fine.
Looks like switching the template to the windows 2016 worked but this appeared to be an issue because before the update the 2019 template worked fine. It also looks like the machines are running way slower than before when I switched to 2016 template.

[dtpoirot]

...be sure and slog through all the options in the 'Turn Windows features on or off' and disable everything which enables Hyper-V...

[scottgus1]

According to the posted vbox.log, Hyper-V is enabled. See HMR3Init: Attempting fall back to NEM (Hyper-V is active).

The bcdedit procedure hits the foundation of all the things in 'Turn Windows features on or off'.