virtualbox.org

This is a friendly Warning:
VirtualBox 6+ NOT compatible with WIN10 Home edition.
I innocently updated to the latest version 6.1.12 in the summer and thought no more of it, then again to 6.1.14 yesterday with extension packs to match.
However the only reason I have VirtualBox it is to run Vauxhall's TIS2000 software which gives you workshop manuals for GM vehicle models up to 2007, and it will only run in XP or Vista. And I only use it a couple of times a year.

Problem is VB6+ auto-defaults to Virtualization On in System/Acceleration settings for x64 Host systems
you the get VT-x is not available (VERR_VMX_NO_VMX
It doesn't matter if your Virtualization Technology is On in your Host BIOS,
It turns out VB6 ALSO requires Hyper-V in your Win10 Home Host
The only way to get Hyper-V in Win10 Home is to upgrade to Win10 Pro/Enterprise or Edu - for a "small" fee of £119 to Microsoft....
after 24hrs of stressing over it I found the simple solution was to Remove VB 6.1.14, reboot then re-install VB 5.2.44
You then reinstall the "downgrade" 5.2.44 extension pack and the Vista rendering of my TIS2000 software came back to life.
The alternative VMware Workstation Player may have worked as well, but it would have also required a full install of your chosen WIn version from a disc which takes too long.
Note to administrators: Please do not allow support for VB 5.2.44 to be switched off.................

Freebeez, I'm afraid you got a few lines crossed in your diagnosis, let's see if we can straighten them out.

Freebeez wrote:VirtualBox 6+ NOT compatible with WIN10 Home edition.

I have run 6.0.x and 6.1.x up to 6.1.12 successfully on Windows 10 Home 1909.

Freebeez wrote:Vauxhall's TIS2000 software .... only run in XP or Vista

6.1.x took away 3D acceleration for XP and Vista due to a massive security hole. If your software requires 3D in XP/Vista, you'll need to stay with 6.0.x or earlier. If no 3D is required, 6.1.x still runs XP & Vista. None of this is altered by Windows Home host OS.

Freebeez wrote:VT-x is not available (VERR_VMX_NO_VMX

This error occurs either because Hyper-V is enabled or you have not turned on VT-x/AMD-V/SVM despite thinking you did.

Windows Home does not have the ability to run Hyper-V virtual machines, but Windows has lots of other non-VM services that have Hyper-V as a backbone, and Home has most if not all of those services. Rest assured, Home has Hyper-V.

Freebeez wrote:VB6 ALSO requires Hyper-V in your Win10 Home Host

Read that spot again. Virtualbox 6.0.x + "can" run under Hyper-V. Virtualbox does not require Hyper-V.
"Can" is in quotes because so far in many cases it can't yet. Virtualbox on Hyper-V is a work in progress, and so far it's been more work than progress, see VirtualBox 6.0 and Hyper-V. Microsoft keeps moving the target.

Forum advice is to confirm Virtualization is on and turn off Hyper-V, see I have a 64bit host, but can't install 64bit guests.