Not able to use Hyper-V as backend with VirtualBox 6.0 on Windows 10

[ShinyCherry]

As the document says "VirtualBox detects Hyper-V automatically and uses Hyper-V as the virtualization engine for the host system", and no configure needed. ​https://docs.oracle.com/cd/E97728_01/F12469/html/hyperv-support.html

But i can't start any virtual machine when Hyper-V feature enabled on my system. I am using Windows 10 version 1903 (Build 18362.53) with VirtualBox 6.0.6 r130049. It says :

(VERR_NEM_MISSING_KERNEL_API).
VT-x is not available (VERR_VMX_NO_VMX).

And logs in attachment

[ShinyCherry]

Here is another error message with 32bit guest.

Raw-mode is unavailable courtesy of Hyper-V. (VERR_SUPDRV_NO_RAW_MODE_HYPER_V_ROOT).

Also different message on different host machine:

Call to WHvSetupPartition failed: ERROR_SUCCESS (Last=0xc000000d/87) (VERR_NEM_VM_CREATE_FAILED).

[ShinyCherry]

Confirm VM started with Windows 10 Version 1809 (Build 17763.107 and 17763.437), but there is only a dash on the top left of screen, It does not boot to install screen.

[thwint]

I have exactly the same error with Virtualbox 6.0.8 and Windows 10 Version 1809, Build 17763.503

[Socratis]

Take a look at the thread in the forums: ​(Solved) Windows 10 Version 1903: Failed to open session; call to WHvSetupPartition failed

BTW, it's usually better and faster, if issues get first addressed in the ​VirtualBox forums, a lot more eyes there. More than 95% of the issues are resolved in the forums, which keeps the developers focusing on the bug fixes and enhancements, and there is no need for another ticket to keep track of.

Plus a discussion and analysis on the bug tracker is going to help me, you, and potentially a future drive-by user or two. Not so in the forums, many more tend to benefit...

[ShinyCherry]

@socratis I am sure i want use Hyper-V as backend of VirtualBox, that thread is a guide to disable Hyper-V for user who don't need it , i can't disable Hyper-V feature since it's more important for me.

[Socratis]

Replying to ShinyCherry:

I am sure i want use Hyper-V as backend of VirtualBox

Then I guess you'll have to wait until both the Microsoft API matures, and the same happens for VirtualBox calling into that API and gets optimized. I know it's not the answer you were looking for...

that thread is a guide to disable Hyper-V for user who don't need it, i can't disable Hyper-V feature since it's more important for me.

As the developers say in their comments, "this might work...":

524	00:00:01.754379 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
525	00:00:01.799597 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work... 

But, the main problem seems to be that something is not enabled in your host:

00:00:01.801071 NEM: NEMR3Init: Native init failed: VERR_NEM_MISSING_KERNEL_API. 

The VERR_NEM_MISSING_KERNEL_API error was prominent during an interaction between the VirtualBox 6.0.x series but with the before the Win10 1809 build. The API from Microsoft wasn't simply there.

I have another thread for you in that case: ​VirtualBox 6.0 and Hyper-V. See if anything there can help you...

[aeichner]

Please reopen if still an issue with latest 6.1.14.