If you get VT-x is not available (VERR_VMX_NO_VMX) error while starting a virtual machine using VirtualBox, then the following solutions will help you resolve the issue. It is pretty common when you disable the virtualization or VT-x before using the VirtualBox virtual machine.
Failed to open a session for the virtual machine [virtual-machine-name]. VT-x is not available. (VERR_VMX_NO_VMX).
You can get this error when starting any virtual machine, including Windows and Linux. Either way, you need to follow the same steps.
VT-x is not available (VERR_VMX_NO_VMX)
To fix VT-x is not available (VERR_VMX_NO_VMX) error, follow these steps:
- Enable VT-x and VT-d
- Disable Hyper-V
- Turn off Hyper-V virtualization using Command Prompt
- Disable Memory integrity
To know more about these steps, continue reading.
1] Enable VT-x and VT-d
When using VirtualBox, VT-x and VT-d are two of the most essential things that need to be enabled on your computer. If your computer doesn’t have these supports, you cannot use VirtualBox and end up getting such an error as stated above. If you enabled it earlier, but it has been disabled mistakenly, you might get the same error. Therefore, it is recommended to turn on the VT-x and VT-d settings from the BIOS.
For that, you need to open the BIOS and find out two settings named Intel Virtualization Technology (also known as VT-x)and VT-d. Following that, you need to verify if they are enabled. If not, turn them on.
2] Disable Hyper-V
When you use VirtualBox, Hyper-V needs to be enabled. Otherwise, you may get such issues mentioned above. As Hyper-V is another virtualization functionality, two virtualization features won’t run simultaneously. Therefore, follow the following steps to disable Hyper-V on your PC:
- Search for windows features in the Taskbar search box.
- Click on the individual search result.
- Find out Hyper-V on the list.
- Remove the corresponding checkbox from the Hyper-V option.
- Click the OK button.
At last, you might need to restart your computer to get the change. Once done, you will be able to use the VirtualBox without any error.
3] Turn off Hyper-V virtualization using Command Prompt
At times, disabling the Hyper-V might not be enough to fix the aforementioned issue. If the same thing happens with you, you need to turn off Hyper-V virtualization using Command Prompt. For that, do the following:
- Search for cmd in the Taskbar search box.
- Click on the Run as administrator option.
- Click the Yes button.
- Enter this command:
bcdedit /set hypervisorlaunchtype off - Enter this command:
dism.exe /Online /Disable-Feature:Microsoft-Hyper-V
After that, you should be able to use VirtualBox with the above-mentioned error message.
4] Disable Memory integrity
You can disable the Memory integrity feature in Windows Security to check if that resolves your issue or not. For that, do the following:
- Search for windows security in the Taskbar search box.
- Click on the individual search result.
- Switch to the Device security tab on the left side.
- Click on the Core isolation details option.
- Toggle the Memory integrity button to turn it off.
After that, restart your computer and check if the problem remains or not.
How do I fix VT-x not available?
To fix VT-x not available, you need to turn on Intel Virtualization Technology from the BIOS. For that, open your BIOS settings, and find out the Intel Virtualization technology option. Next, make sure that it is turned on. If not, toggle the option to turn it on.
Read: VT-x is disabled in the BIOS for all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)
How do I enable VT-x on a VM?
To enable VT-x on a VM or virtual machine, you need to enable the Intel Virtualization Technology. To do so, open the BIOS on your computer and find out the Intel Virtualization Technology option. Then, you need to select the Enabled option.
