﻿id	summary	reporter	owner	description	type	status	component	version	resolution	keywords	cc	guest	host
20621	Hyper-V doesn't work on AMD Ryzen 3800x for old VM	vbicf		"Hi,

I have some old Windows 10 VM (VT-X) that was created when Hyper-V was not enabled in the host. After I enable Hyper-V, that old VM will not start and it will get a bluescreen. Is there a way to fix that old VM machine so that it will start with Hyper-V enabled in the host. I changed the settings in VirtualBox to use Hyper-V Paravirtualization but the blue screen happens again. See here:

If I create a VM from scratch with Hyper-V enabled in the host, the VM will boot fine.

This means something in the old VM is causing the crash. I don't want to reinstall it from scratch.

System: Ryzen 3800X

The version of VirtualBox: 6.1.26

Host: Windows 10 21H1, Guest: Windows 10 20H2

When the VM was created: VT-x/AMD-V enabled, HyperV disabled

installed Guest Additions and Host Extensions

I have another system Intel 7700k, on that system with the same VM I can start that old VM when Hyper-V is enabled!

This looks like and AMD specific issue.

I am attaching the log from my amd system when I get the blue screen.
"	defect	closed	other	VirtualBox 6.1.26	fixed			Windows	Windows
