Launch Oracle VM VirtualBox can be blocked by the Windows system hypervisor, which intercepts processor resources even before the program starts. If you see an error when trying to open a virtual machine VERR_VM_DRIVER_NOT_INSTALLED or a message about the inability to start VT-x/AMD-V, this means that there is a conflict in virtualization technologies in the system. Most often the problem lies in the active components Hyper-V or a disabled function in the BIOS, which does not allow VirtualBox Gain direct access to hardware resources.
For correct operation, you need to consistently check the BIOS/UEFI settings of your motherboard and eliminate software conflicts in the operating system. Unlike native Windows tools, VirtualBox requires exclusive access to processor instructions to emulate hardware. Ignoring these requirements results in 64-bit guest OSes simply not loading, even if the disk image is working.
In this guide, we will look at how to force necessary services to be enabled, disable interfering components, and correctly configure startup parameters for stable operation of the virtual environment. You will find out which items need to be activated in (Control Panel) and how to check the virtualization status via the command line. It is critical to complete all steps in order, as skipping one step in BIOS setup may negate all software changes.
Checking virtualization support in BIOS/UEFI
The first step before turning on VirtualBox, you need to make sure that virtualization technology is activated at the hardware level. Without this, the software will not be physically able to create isolated environments. On processors Intel this function is called Intel Virtualization Technology or VT-x, and on chips AMD — SVM Mode or AMD-V.
To enter the BIOS settings when the computer boots, press the key F2, Del or F10 (depending on the motherboard manufacturer). Find a section that might be called Advanced, CPU Configuration or Security. There should be a switch that needs to be set to Enabled. After saving the settings and rebooting, the system will be ready to work with hypervisors.
⚠️ Attention: If after enabling this option the computer stops loading the operating system or starts beeping, immediately return the setting to its original position. In rare cases, on very old hardware, activating virtualization may cause driver conflicts.
You can check whether virtualization is activated without rebooting using the Windows Task Manager. Click Ctrl + Shift + Esc, go to the tab Productivity and select CPU. In the lower right corner there should be an inscription “Virtualization: Enabled”. If it says "Disabled", then VirtualBox will not be able to run 64-bit systems, and you definitely need to go into the BIOS.
- 🔍 Restart your computer and enter BIOS/UEFI (Del, F2, F10 keys).
- 🔍 Find the Advanced or CPU Configuration section.
- 🔍 Activate Intel VT-x or AMD SVM (Enabled).
- 🔍 Save changes (F10) and boot Windows.
How to find BIOS settings on different laptops
On HP laptops you often need to press F10, on Lenovo - F1 or Fn+F2. Some Acer models require you to first press F2 and then Enter. If the standard keys do not work, try holding Esc while turning on to see the boot device selection menu, where there is often an entry to Setup.
Resolving conflicts with Hyper-V and other hypervisors
The most common reason why you cannot turn on VirtualBox on Windows 10 and 11, there is a conflict with the native hypervisor Microsoft Hyper-V. When this component is active, it seizes control of the processor, preventing VirtualBox use hardware virtualization directly. As a result, the program either does not start or runs extremely slowly, emulating the processor using software methods.
To resolve the situation, you must completely disable the Windows virtualization platform. This is done through the standard system components window. Open the Start menu, type "Turn Windows features on or off" and launch the found item. In the list that opens, you need to find and uncheck the following items:
- 🚫 Hyper-V
- 🚫 Virtual Machine Platform
- 🚫 Windows Sandbox
- 🚫 Windows Subsystem for Linux (WSL)
After removing the marks, the system will require a reboot. Only after restart VirtualBox will be able to correctly initialize its drivers. If you are using Docker Desktop or WSL 2, keep in mind that they also require Hyper-V. In this case, you will have to choose: either work through native Microsoft tools, or classic VirtualBox. Collaboration is only possible in compatibility mode, which reduces performance.
☑️ Checking Hyper-V conflicts
Configuring virtual machine startup options
After eliminating system conflicts, it is important to properly configure the virtual machine itself before the first launch. When creating a new car in the menu VirtualBox It is critical to select the correct version of the operating system. If you specify "Windows 7" and try to run a "Windows 10" image, the program may not include the necessary processor instructions and the installation will fail.
Pay special attention to the section System in the machine settings. There is a tab here Motherboard, where you need to check the chipset and, most importantly, the boot order. Make sure that the first device in the list is Optical disc (if you are installing the system from an ISO image) or Hard drive (if the system is already installed). The controller is also activated here I/O APIC, necessary for multiprocessor systems.
| Setting option | Recommended value | Impact on work |
|---|---|---|
| Chipset | PIIX3 (for old OS) / ICH9 (for new ones) | Determines hardware compatibility |
| Number of processors | 1 or 2 (no more than 50% of host cores) | Affects speed and stability |
| Memory size | Green slider area (usually 2048-4096 MB) | Insufficient memory will cause errors |
| Enable EFI | Only for macOS or new Linux/Windows | Required to boot UEFI systems |
In the section Display be sure to increase the video memory to the maximum value (usually 128 MB) and enable 3D acceleration. Without this, the guest OS interface may experience delays and the screen resolution will be limited to a small window. For GUIs Linux and modern versions Windows This is a mandatory requirement for comfortable work.
Run via command line and PowerShell
Sometimes GUI VirtualBox does not respond to launch commands, and then the command line comes to the rescue. This method allows you to launch a virtual machine in the background or with special parameters, bypassing possible interface bugs. The utility is used for this VBoxHeadless or command VBoxManage.
Open Command Prompt as Administrator. Go to the program installation directory, usually this C:\Program Files\Oracle\VirtualBox\. To start a specific machine, use the following construct:
VBoxManage startvm"Your_Machine_Name" --type headlessParameter --type headless means that the machine will start without a graphical console window, which is useful for servers. If you need the full interface, replace headless on gui. This method often helps diagnose errors: if the error text is displayed on the command line, it is easier to copy it and find a solution than to understand the codes in the GUI pop-ups.
Use the `VBoxManage list vms` command to see the exact names of all registered virtual machines. Names are case sensitive and must be enclosed in quotes if they contain spaces.
Solving common startup errors
Even with proper configuration, users encounter specific error codes. One of the most popular - VERR_NEM_NOT_AVAILABLE. It means that VirtualBox tries to use the NEM (Native Execution Manager) engine, but cannot find the necessary system libraries. The solution lies in the settings of the virtual machine itself: go to System -> Acceleration and select the paravirtualization interface Default or Hyper-V, if disabling the hypervisor is not possible.
Another common problem is error NS_ERROR_FAILURE at startup. This often occurs if you try to start a machine that was shut down incorrectly last time, or if the configuration file .vbox damaged. In this case, creating a Snapshot before starting or deleting the file helps .vbox-prev in the machine folder.
⚠️ Attention: Never delete files with the extension
.vdior.vmdkin the virtual machine folder. These are your virtual hard drives with all your data. The startup error can be solved by settings, not by removing the disk.
If the error is related to the network (Failed to open/create the internal network), try disabling the network adapter in the machine settings before starting. Sometimes the driver VirtualBox does not have time to boot together with the host network card. After successfully starting the machine, the adapter can be turned back on through the menu Devices -> Network.
Optimizing performance after enabling
When you managed to turn on VirtualBox and boot the guest OS, it may seem slow. This is normal for out-of-the-box condition. To speed up the work, be sure to install Guest Additions. This is a set of drivers and utilities that allows a virtual machine to efficiently use the resources of your real computer.
From the running virtual machine menu, select Devices -> Mount Guest Additions disk image. A virtual CD with the installer will open inside the guest OS. Run VBoxWindowsAdditions.exe (for Windows) or run the install command for Linux. After this, a shared clipboard, dragging files (Drag'n'Drop) and dynamically changing screen resolution will become available.
- 🚀 Install Guest Additions immediately after the first OS boot.
- 🚀 Dedicate no more than 50% of the host processor cores to the virtual machine.
- 🚀 Use SSD to host virtual disk files.
- 🚀 Disable unnecessary devices (USB, Audio) if they are not needed.
It's also worth checking the host's power settings. If the laptop is running in power saving mode, the processor reduces the frequency, which has a catastrophic effect on virtualization performance. Switch the power plan to High performance while working with VirtualBox.
The main secret of stability: always turn off the virtual machine through the guest OS menu ("Shutdown"), and do not close the program window. Forcibly closing a window is equivalent to pulling out the power cord from a real computer.
Why doesn't VirtualBox see the ISO image on startup?
Most often the problem is that the image is not “inserted” into the virtual drive. Go to Machine Settings -> Media. Select an empty disk with the CD icon, and in the "File" field on the right, select your ISO file. Make sure that the "Live Kernel" (Live CD/DVD) checkbox does not conflict with the boot settings.
Is it possible to run VirtualBox and VMware at the same time?
Technically this is possible, but it is highly not recommended. Both hypervisors are trying to grab CPU resources. This will lead to severe brakes on both systems or the collapse of one of them. It is better to use only one virtualization tool on your computer.
How to increase the size of a virtual disk if it is full?
In the machine settings, you cannot simply change the size slider. You need to use the command VBoxManage modifyhd to expand the disk file, and then inside the guest OS expand the partition through "Disk Management". Simply changing settings in the GUI will not add space to the disk itself.
What should I do if my mouse cursor gets stuck inside a virtual machine?
By default, you need to press right to exit the cursor. Ctrl (Host Key). To have the cursor released automatically, install Guest Additions. This will enable pointer integration, and the mouse will automatically switch between windows without holding down keys.
Is it safe to use VirtualBox for virus testing?
Yes, if isolation is maintained. Be sure to disable the "Network Bridge" (Bridged Adapter) and use NAT mode or an isolated network. Also disable shared folders and the clipboard to prevent the virus from spreading to the main system. Take a snapshot before running the infected file.