The error message from Virtualbox reads:
"Cannot enable nested VT-x/AMD-V without nested-paging and unresricted guest execution!
Encountered this error when trying to run any VM under VirtualBox Version 6.0.12 r133076 (Qt5.6.2). I’m assuming all versions of VBox are affected when running under Windows 10.
Looking around the web found this reddit post where this solution is proposed:
PS C:\Windows\system32> bcdedit /set hypervisorlaunchtype off
On my system (Windows Version 10.0.18362.329) it didn’t ask for a reboot but even after rebooting VirtualBox still didn’t work. That’s when I remembered I had enabled the Virtual Machine Platform option in the “Turn Windows Features on or off” section of Programs and Features. Disabling this feature and rebooting allowed Virtualbox VMs to boot without issues.
Here’s how to disable the option through PowerShell with Admin rights:
PS C:\Windows\system32> Disable-WindowsOptionalFeature -online -FeatureName VirtualMachinePlatform
I’m not sure if other Hyper-V options would affect VirtualBox in the same way but it’d seem they do. Posting up here mostly so it doesn’t get lost in social media link morass.