What ELSE conflicts with VirtualBox on Windows 10?

[davhunter]

I've installed VirtualBox on a Windows 10 host, with a 64-bit processor and the correct virtualization BIOS settings enabled, and I do not have Hyper-V installed. I have disabled DeviceGuard/CredentialGuard, and I've installed VirtualBox as Administrator. Still, however, I can't create 64-bit VMs, and the Acceleration tab is greyed out.

How can I troubleshoot what else might be conflicting with VirtualBox, preventing it from taking advantage of the CPU's virtualization capabilities? Every post I've ever seen on this topic talks about disabling Hyper-v, but what if Hyper-v isn't the culprit -- what else might it be, and how do I find out?

[socratis]

There's no known recipe to find what's using Hyper-V VT-x exclusively, only guidance. Debuggers, antivirus, emulators, etc. You got to go through each and every suspect in your programs to know for sure.

EDIT: Fixed "Hyper-V" to "VT-x" after BillG's comment.

[BillG]

@socratis, I think you meant to say hardware virtualization, not Hyper-V.

@davhunter, I think you did as well. What you are talking about is what prevents VirtualBox from accessing hardware virtualization. That is what is blocked, not VirtualBox.

[socratis]

@socratis, I think you meant to say hardware virtualization, not Hyper-V.

Correct in the broader sense. Fixed in the post, thanks BillG.

[davhunter]

It took quite a while, but I finally managed to remove the VT-x hog; in my case, even though Hyper-V wasn't running, Device Guard and Credential Guard were. Removing them removed the conflict, allowing VirtualBox to use the CPU's VT-x capabilities.

For those who are having similar problems, Microsoft provides a PowerShell tool for readying a system to install DG and CG, which can also be used to remove them. Googling "Device Guard and Credential Guard hardware readiness tool" will help you find it.