The issue where Ubuntu 24.04 fails to boot in VirtualBox 7.1.3 on Windows 11, often stuck on the GRUB menu or memtest screen, is typically caused by incompatible graphics controller settings or missing virtualization extensions. Ensuring that Intel VT-x/AMD-V is enabled in your BIOS and selecting the correct display controller within the VirtualBox machine settings resolves the majority of these boot loops.
Verifying Hardware Virtualization
Before modifying VirtualBox settings, you must confirm that your host system supports and has enabled hardware virtualization. Without this feature, the hypervisor cannot run nested operating systems efficiently, leading to hangs during the boot process.
- Open the Task Manager on Windows 11 by pressing
Ctrl + Shift + Esc.
- Navigate to the Performance tab and select CPU.
- Look for "Virtualization" at the bottom right. It should say "Enabled".
If it shows "Disabled", you need to restart your computer and enter the BIOS/UEFI setup (usually by pressing F2, Del, or F10 during startup). Locate the Virtualization Technology setting (often labeled Intel VT-x, AMD-V, or SVM Mode) and enable it. Save changes and reboot into Windows before attempting to start the VM again.
Adjusting Graphics Controller Settings
The most common culprit for the Ubuntu boot loop in VirtualBox 7.1.x is the default graphics controller configuration. Newer versions of VirtualBox have changed default behaviors that may conflict with the guest OS's expectations.
Navigate to the VirtualBox Manager and select your Ubuntu virtual machine. Click on "Settings" and go to the "Display" section. Under the "Screen" tab, look for the "Graphics Controller" dropdown. If it is set to "VMSVGA", try changing it to "VBoxSVGA" or "VBoxVGA". Conversely, if it is already one of those, switching to VMSVGA might help. This change forces the virtual GPU to use a different driver interface that the Ubuntu kernel can initialize correctly during early boot stages.
Additionally, ensure the "Graphics Memory" is set to at least 128 MB. Low video memory allocation can cause the display server to fail initialization, resulting in a black screen or frozen GRUB menu. After making these changes, click OK and attempt to start the machine.
Checking EFI and Secure Boot Configuration
Ubuntu 24.04 relies heavily on UEFI and Secure Boot features. If these are not properly configured in the virtual environment, the bootloader may hang while waiting for authentication or hardware checks.
In the VirtualBox Settings for your VM, go to the "System" tab and then the "Motherboard" sub-tab. Ensure that "EFI" is checked if your Ubuntu installation was created as an EFI system. For older installations using Legacy BIOS, uncheck EFI.
Furthermore, check the "Processor" tab under "System". Make sure "Enable PAE/NX" is checked. This allows the CPU to handle modern security features required by recent Linux kernels. If you are experiencing issues specifically with the GRUB menu appearing but not proceeding, verify that the "Boot Order" in the same tab lists Hard Disk as the primary boot device, rather than Optical or Network.
For more insights on managing virtual machines effectively, see
Unable to add existing virtual machines in VirtualBox.
Reinstalling Guest Additions
Once Ubuntu successfully boots, installing the VirtualBox Guest Additions is crucial for proper performance and display resolution. However, failed installations of these additions can sometimes cause boot failures on subsequent reboots.
Shut down the Ubuntu VM completely. In the VirtualBox Manager, go to Devices > Insert Guest Additions CD image. Inside Ubuntu, open the terminal and mount the CD:
sudo mount /dev/cdrom /mnt
cd /mnt
sudo ./VBoxLinuxAdditions.run
If the installation fails due to missing kernel headers, install them first:
sudo apt update
sudo apt install build-essential dkms linux-headers-$(uname -r)
After running the installer, reboot the VM. This step ensures that the virtualized drivers for audio, networking, and graphics are correctly loaded, preventing potential conflicts that could mimic boot errors.
Clearing Corrupted State Files
Sometimes, the virtual machine's state files become corrupted after an improper shutdown, causing it to resume in a broken state rather than starting fresh.
Locate the folder where your VirtualBox virtual machines are stored on your Windows 11 host. Find the folder corresponding to your Ubuntu VM. Look for files ending in
.sav or
.lock. Delete these files carefully. The
.sav file contains the saved state of the VM from the last session; removing it forces VirtualBox to perform a cold boot instead of resuming a potentially corrupted session.
If the problem persists, consider creating a new virtual machine with identical specifications (RAM, CPU cores, disk size) and attaching the existing hard disk image (
.vdi) to it. This isolates whether the issue lies with the VM configuration metadata or the disk image itself.
For users interested in other Linux distributions on Windows,
Kubuntu Not Running Inside Windows 11 in VirtualBox offers similar troubleshooting steps for KDE-based environments.
Frequently Asked Questions
Why does my Ubuntu VM freeze at the GRUB menu?
This usually indicates that the graphics driver is failing to load during the initial boot sequence. Switching the graphics controller from VMSVGA to VBoxSVGA in the Display settings often resolves this compatibility issue.
Can I use UEFI with an older Ubuntu version?
Yes, but you must create the virtual machine with the EFI checkbox enabled from the start. Converting a legacy BIOS VM to UEFI later is complex and may require reinstalling the bootloader manually.
What if VirtualBox says "VT-x is not available"?
This means hardware virtualization is disabled in your computer's BIOS/UEFI. You must restart your physical machine, enter the firmware settings, and enable Intel VT-x or AMD-V under the CPU configuration options.
Does disabling Secure Boot fix boot issues?
Disabling Secure Boot in the VM's System settings can help if the Ubuntu ISO signature verification is failing. However, Ubuntu 24.04 expects Secure Boot to be active for full security compliance, so only disable it as a diagnostic step.
How do I recover if the VM won't start at all?
Try booting from the Ubuntu Live ISO attached to the optical drive. If the live environment loads, the issue is likely with the installed OS bootloader or disk permissions rather than the VirtualBox configuration itself.