Nested virtualization allows you to run Hyper-V inside a VM, opening up incredible flexibility for testing complex infrastructure setups, demos, or learning environments, all without extra hardware.
First, ensure you’re running a Hyper-V host capable of nested virtualization and have the Windows Server 2025 VM on which you want to enable as a Hyper-V host ready.
To get started, open a PowerShell window on your Hyper-V host and execute:
Set-VMProcessor -VMName "<Your-VM-Name>" -ExposeVirtualizationExtensions $true
Replace <Your-VM-Name> with the actual name of your VM.
This command configures Hyper-V to allow nested virtualization on the target VM.
Boot up the Windows Server 2025 VM that you want to configure as a Hyper-V host. In the VM, open Server Manager and attempt to install the Hyper-V role via Add Roles and Features. Most of the time, this should work right away. However in some cases you might hit an error stating:
“Hyper-V cannot be installed because virtualization support is not enabled in the BIOS.”
To resolve this error run an elevated PowerShell session inside the VM on which you want to enable Hyper-V and run the command:
bcdedit /set hypervisorlaunchtype auto
This command ensures the Hyper-V hypervisor starts up correctly the next time you boot.
Restart your VM to apply the change. After the reboot, head back to Add Roles and Features and try installing Hyper-V again. This time, it should proceed smoothly without the BIOS virtualization error.
Once Hyper-V is installed, perform a final reboot if prompted. Open Hyper-V Manager inside your VM and you’re now ready to run test VMs in your nested environment!
Microsoft