virtualbox.org

Hi,
I am really sorry for asking about this - so many times answered question - but I am already desperate about it, loosing hours of time spent on the
issue. I have reviewed all related threads and tried most of suggested solutions. No success.

Today's morning, after restarting my corporate laptop, my Virtualbox 6.1.14 (now upgraded to 6.1.16) started to complain about VT-x being not
available (anymore). I checked all settings, started from Bios (VT-x enabled) through Window's Hyper-V (deactivated), Windows Defender Application Guard (disabled withgpedit DeviceGuard and CredentialGuard), disabled fast-boot, verified if "Core Integrity" is properly disabled. Still there is the problem.

Can somebody else look at this? I am clueless, there is a hope someone with a fresh look/head can spot something obvious in it:
I have attached the VBox.log and the VBoxHardening.log - and will be thankfull for any hint.
Thank you,
Jurek

It looks like you did a good hunt on all fronts, but the log thinks that either your PC BIOS does not have the "Virtualization Technology" (VT-x/AMD-V/SVM) turned on, or something on the PC, like Hyper-V or 3rd-party antivirus, is interfering. Go through every part of
I have a 64bit host, but can't install 64bit guests.

FWIW the log has half of the tell-tale "Hyper-V is on" message before the posted error message:

00:00:07.949811 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available

Yeah you're right. Finally I stumbled over "System Information" utility which plainly reports something unexpected at the bottom
No clue how it is enforced so far. Next step is to compare that at my buddies' machines where I suspect to find it deactivated.
Anyway it is not VirtualBox problem.

Yep - credential guard will do it.

Even if you have a problem like that, you can still run VirtualBox normally if you prevent the hypervisor from loading using the bcdedit command (as described in the various guides). The hypervisor is the real problem, not the various things which require it.

I have a Windows 10 with fully functioning Hyper-V installation which I use to test what vms have problems running in VirtualBox under those conditions. Everything works normally (except Hyper-V) if the hypervisor does not load.

Were you able to resolve this.
I have similar problem.

Smita, when you want to add on an existing topic that you think applies to you, you're supposed to try the advice in the topic first.

Did you read this topic first before posting? Did you do what it says to do?