Not in a Hypervisor Partition (HVP=0): How to Fix the VirtualBox Error on Windows

Applies to: Oracle VirtualBox on Windows 11 and Windows 10, when a virtual machine won’t start and the error details mention HVP=0, VERR_NEM_NOT_AVAILABLE, VERR_VMX_MSR_ALL_VMX_DISABLED or VERR_VMX_NO_VMX.

What the error means

VirtualBox can run virtual machines in two ways on Windows. Normally it uses the processor’s virtualization features (Intel VT-x or AMD-V) directly. If Windows’ own hypervisor (the one behind Hyper-V, WSL 2 and some security features) is running, VirtualBox can instead run through Microsoft’s Windows Hypervisor Platform API, which VirtualBox calls NEM.

The message “Not in a hypervisor partition (HVP=0)” means VirtualBox checked for the Windows hypervisor and didn’t find it, so the NEM route isn’t available. On its own that’s fine, but it appears in the error because the direct route failed too, which is what the second line tells you:

Second error line	What it usually means
VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)	Virtualization is switched off in the BIOS/UEFI. Go to Fix 1.
VT-x is not available (VERR_VMX_NO_VMX)	The processor doesn’t offer VT-x to Windows: it’s off in firmware, the CPU doesn’t support it, or Windows itself is running inside a VM. See Fix 1 and Fix 5.
AMD-V is disabled in the BIOS (or by the host OS) (VERR_SVM_DISABLED)	The AMD equivalent: turn on SVM Mode in the BIOS/UEFI (Fix 1).

Check whether virtualization is on

Open Task Manager with Ctrl + Shift + Esc, go to Performance and select CPU. Below the graph, Virtualization shows Enabled or Disabled.

You can also run systeminfo in Command Prompt and look at the last section. Virtualization Enabled In Firmware: No means it’s off in the BIOS. If it says A hypervisor has been detected, the Windows hypervisor is running, which matters for Fix 2.

Fix 1: Turn on VT-x or AMD-V in the BIOS/UEFI

1. Save your work. Open the firmware settings from Windows: on Windows 11 go to Settings > System > Recovery; on Windows 10 go to Settings > Update & Security > Recovery.
2. Next to Advanced startup, select Restart now.
3. Choose Troubleshoot > Advanced options > UEFI Firmware Settings, then Restart. (On older PCs, press the setup key, such as F2, F10 or Del, while the PC starts.)
4. Find the virtualization setting. It’s usually under Advanced, CPU Configuration or Security and is called Intel Virtualization Technology, Intel VT-x or VMX on Intel PCs, and SVM Mode or AMD-V on AMD PCs.
5. Set it to Enabled, save the changes (often F10) and let the PC restart.
6. Check Task Manager again, then start the virtual machine.

The exact menu names vary by PC maker, so check your PC or motherboard manual if you can’t find the option. If your fTPM or other firmware settings change after a BIOS reset, see new CPU installed, fTPM/PSP NV corrupted.

Fix 2: Decide how VirtualBox and Hyper-V should share

If virtualization is already enabled in the firmware, the Windows hypervisor is the next thing to check. These Windows features turn it on:

• Hyper-V
• Virtual Machine Platform (used by WSL 2)
• Windows Hypervisor Platform
• Windows Sandbox
• Memory integrity under Windows Security > Device security > Core isolation details (it uses virtualization-based security)

You then have two options:

1. Keep WSL 2, Docker or Hyper-V: press Win + R, type optionalfeatures, tick Windows Hypervisor Platform, select OK and restart. VirtualBox then runs through Hyper-V. This works with current VirtualBox versions, but virtual machines can be noticeably slower and some guest features may not work.
2. Give VirtualBox the processor directly: turn the Windows hypervisor off (Fix 3). VirtualBox runs at full speed, but WSL 2, Windows Sandbox, Hyper-V virtual machines and Memory integrity stop working until you turn it back on.

Fix 3: Turn off the Windows hypervisor for VirtualBox

Only do this if you chose option 2 above. Open Command Prompt as administrator and check the boot setting first:

bcdedit /enum | findstr -i hypervisorlaunchtype

If it shows Auto, turn it off and restart:

bcdedit /set hypervisorlaunchtype off

To go back later (for example to use WSL 2 again), run bcdedit /set hypervisorlaunchtype auto and restart. Microsoft’s WSL troubleshooting guide uses this same setting to turn the hypervisor back on.

If the hypervisor still starts, untick the features listed in Fix 2 in optionalfeatures and turn off Memory integrity, then restart. Memory integrity is a security feature, so turn it back on when you no longer need VirtualBox this way. Some work PCs enforce it through policy; ask your IT team rather than working around it.

If editing the boot configuration gives errors, see Windows RE image was not found for how to check boot and recovery settings safely.

Fix 4: Update VirtualBox

Older VirtualBox versions handle Hyper-V and newer processors less well. Download the latest version from virtualbox.org, install it over the old one (your virtual machines are kept), restart, and install the matching Extension Pack if you use it.

Fix 5: Enable nested virtualization inside a VM

If the Windows PC running VirtualBox is itself a virtual machine (for example in Hyper-V, VMware or a cloud service), it won’t see VT-x unless the outer hypervisor passes it through. On a Hyper-V host, shut the VM down and run this in an administrator PowerShell on the host:

Set-VMProcessor -VMName "<VMName>" -ExposeVirtualizationExtensions $true

In VMware Workstation, the matching option is Virtualize Intel VT-x/EPT or AMD-V/RVI in the VM’s Processors settings. Cloud VMs only support this on certain machine types.

Related guides

• New CPU installed, fTPM/PSP NV corrupted: what to choose
• Windows RE image was not found: how to fix it
• WHEA_UNCORRECTABLE_ERROR: how to fix it

Official sources: for more detail, see the official documentation:

• Microsoft Support: Enable virtualization on Windows
• Microsoft Learn: Troubleshooting WSL (hypervisor launch and virtualization settings)

Frequently asked questions

What does HVP=0 mean?

It means Windows is not running inside the Hyper-V hypervisor, so VirtualBox can’t use the Windows Hypervisor Platform route. It’s only a problem when VirtualBox also can’t use VT-x or AMD-V directly, which the next error line explains.

Is it safe to enable virtualization in the BIOS?

Yes. It’s a standard setting that Windows features such as WSL 2 and Windows Sandbox also need. It doesn’t slow the PC down when nothing is using it.

Can I use VirtualBox and WSL 2 at the same time?

Yes, with Windows Hypervisor Platform turned on (Fix 2, option 1). Expect lower virtual machine performance than with the hypervisor off.

My PC doesn’t have a virtualization option in the BIOS. What now?

Check for a BIOS update from your PC maker, since some add the option later. Very old processors may not support VT-x or AMD-V at all, and current VirtualBox versions need hardware virtualization to run any virtual machine.