[Solved] Cannot start any VM

[felixd]

I had some VMs running a few months ago, and now I can't get any Vm to boot up. Neither old ones nor newly created ones.

I always get the same error:

(VERR_NEM_MISSING_KERNEL_API).

VT-x is not available (VERR_VMX_NO_VMX).

This is my system and what I tried:
(I cannot post URLs since I am new to the community)

See the screenshots below:
- I have Hyper-V disabled
- Virtualization is supported on my CPU (and it is enabled in the BIOS/UEFI)
- Core Isolation (windows Defender/Security) is enabled, but Memory integrity is off:

I have already disabled Norton Security, rebooted multiple times, enabled and disabled Hyper-V, uninstalled Virtualbox 5 and now installed Virtualbox 6.0.4. Nothing had worked.

What could I be doing wrong? Any suggestions?

[socratis]

Please go thoroughly through the FAQ: I have a 64bit host, but can't install 64bit guests. Remember that these are just guidelines, you have to use your judgement...

And can you please edit your message and attach the images here, locally?

[felixd]

I have read the FAQ another time, and checked that I did everything. And I added the images. Thank you for the hint, I had overseen it last time.

I could now manage to create a new VM (Ubuntu 18.04 Desktop iso), that sort of starts, but then hangs. Old VMs cant't be launched, although having the same config.

[socratis]

It seems that you have Hyper-V enabled. You can tell from the status bar where the "slow" icon shows:

And no, I don't mean the "Hyper-V" checkbox that's cleared. i mean a little bit further down the list, the "Windows Hypervisor Platform". Uncheck that and try again. If you are successful and VirtualBox is running without Hyper-V enabled, then the standard virtualization icon would show:

[BillG]

I would also disable Virtual Machine Platform if Hyervisor Platform does not fix it.

Where did all those features come from? Are you running Enterprise?

[socratis]

I would also disable Virtual Machine Platform

Good call BillG, I wasn't even aware of that one!

[felixd]

Weeehee!

Disabling Virtual Machine Platform fixed it! I could've sworn I had tested it without that one, but later thought it was probably needed vor Virtualbox. Thanks a lot!

[socratis]

Great, thanks for letting us know. And thank you for marking the topic as [Solved]...