Performance issues, can't stop Hyper-V

[abc12346]

I have same problem: when creating/running a vm while "A hypervisor has been detected" under systeminfo, the vm is always green turtled. Last night I uninstalled the virtualbox, tried all the hyper-v disable thing, power off and reboot after 2 minutes, and finally I come up with a case when "A hypervisor has been detected" is not shown. I was then able to install virtualbox and then a ubuntu 20.04.4 image without a problem. I installed some programs I need in the ubuntu, including a trick to make the window scaling (See https://www.youtube.com/watch?v=x5MhydijWmc at 16'45"), and everything worked perfectly. I then saved the vm image and exit, and reboot the PC. Then when I restart the vm using the saved image, I noticed a quick "can't read xxx" error message flashed, and the vm is green-turtled again!

I can't make the green turtle go away so tried the same things again: close all running programs, uninstall virtualbox, set the hyper-v off and poweroff stuff, but I can not get rid of "A hypervisor has been detected" anymore even after 3 tries. And of course trying to install a vm immediately shows a green turtle even in the setup stage.
Does anybody know how to find the "hypervisor that has been detected" so I can do something about it?
My setup: Dell Precision 5560 with windows 10 Enterprise. Version: 20H2, OS build: 19042.685, Experience: Windows Feature Experience Pack 120.2212.551.

Swipe the whole PC and reinstall may work, but it is way too much work. And there is no guarantee it won't happen again, unless I can find the program/service that started the hypervisor, and stop the program/service.

Thanks.

[scottgus1]

In HMR3Init: Attempting fall back to NEM (Hyper-V is active) is an explanation of what to do if you cannot get Hyper-V turned off, and something that may prevent you getting Hyper-V turned off, which something might be implied by:

Dell Precision 5560 with windows 10 Enterprise.

Split to a separate topic.

[abc12346]

Thanks all for the help. I was able to solve this problem by following the following instruction from https://docs.microsoft.com/en-us/window ... ard-manage

Code: Select all

Delete the following registry settings:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\LSA\LsaCfgFlags
...
If you also wish to disable virtualization-based security delete the following registry settings:

HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\DeviceGuard\EnableVirtualizationBasedSecurity
...

I was kind of afraid to manually edit the register entry since I don't know exactly what it mean and very hard to remember how to revert back later. The value I deleted was 0 which is equivalent to no hyper-v so i did not think I should delete it before. I was desperate yesterday so I deleted them. And now green turtle is gone after reboot.

[abc12346]

Oh no! the problem happens again! After reboot, systeminfo under cmd.exe shows A hypervisor is detected again, which makes the virtualbox VM a second tier citizen and thus the green turtle.
Is there any way to find out which service that triggered the hypervisor?
Thank you!

[Martin]

Is your PC "standalone", or is it member of a domain managed by other administrators?