Blog

How to Fix Hyper-V Assembly Not Found Error on Windows 11: Step-by-Step Solutions

If you are trying to use Hyper-V on Windows 11 and encounter an “Assembly Not Found” error, you are not alone. This error can prevent Hyper-V from running correctly. Fortunately, there are simple ways to fix it.

This guide will walk you through detailed, easy-to-follow steps to resolve the issue. No advanced technical knowledge is required, and each step explains why it is important.

By following these instructions carefully, you can get Hyper-V up and running smoothly again. Let’s start with some quick checks before diving into the fixes.

Understanding the cause of the error helps in applying the right solution quickly.

Quick Note: Prerequisites and Basic Checks

  • Check Windows Version: Make sure you are running Windows 11 Pro, Enterprise, or Education editions because Hyper-V is not available on Windows 11 Home by default.
  • Verify Hardware Support: Confirm your PC supports virtualization technology (Intel VT-x or AMD-V) and that it is enabled in the BIOS/UEFI settings.
  • Update Windows: Ensure your Windows 11 is fully updated. Sometimes, missing system updates cause compatibility errors.
  • Run as Administrator: When working with Hyper-V tools, always run Command Prompt or PowerShell as an administrator to avoid permission issues.

Step 1: Enable Hyper-V Feature Properly

The “Assembly Not Found” error can occur if Hyper-V is not fully or correctly enabled in Windows features. Here’s how to check and enable it:

  1. Press Windows + R to open the Run dialog.
  2. Type optionalfeatures and press Enter. This opens Windows Features.
  3. Scroll down and locate Hyper-V. Make sure the checkbox is fully ticked, including all sub-items like Hyper-V Management Tools and Hyper-V Platform.
  4. If it’s unchecked or partially checked, check it fully, then click OK.
  5. Windows will apply the changes and ask you to restart your PC. Restart to finalize the setup.

Why this matters: Hyper-V needs to be completely enabled for all its components to work. Partial installation can lead to missing assembly errors.

Step 2: Repair System Files Using SFC and DISM

Corrupted system files can cause the assembly error. Windows provides built-in tools to scan and fix these files:

  1. Open Command Prompt as an administrator: Search for “cmd,” right-click it, and select Run as administrator.
  2. Type the following command and press Enter:
    sfc /scannow
  3. Wait for the scan to finish. It will automatically fix problems it detects.
  4. Next, type these commands one by one, pressing Enter after each:
    DISM /Online /Cleanup-Image /ScanHealth
    DISM /Online /Cleanup-Image /RestoreHealth
  5. Once these complete, restart your PC and try using Hyper-V again.

Why this matters: System file corruption is common and can break essential components Hyper-V relies on.

Step 3: Reinstall Hyper-V Using PowerShell

If enabling Hyper-V via Windows Features doesn’t fix it, try reinstalling Hyper-V using PowerShell commands. This method can reset any broken installations.

  1. Open Windows PowerShell as administrator.
  2. Type this command to uninstall Hyper-V completely:
    Disable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V-All
  3. Restart your computer after this process.
  4. After restart, open PowerShell as admin again.
  5. Now, reinstall Hyper-V with this command:
    Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V -All
  6. Restart your PC once more to complete the process.

Why this matters: Reinstalling Hyper-V ensures all necessary files and configurations are refreshed, often fixing assembly-related issues.

Step 4: Check and Update .NET Framework

Hyper-V relies on certain .NET Framework components. A missing or outdated .NET installation can cause assembly errors.

  1. Press Windows + R, type appwiz.cpl, and press Enter to open Programs and Features.
  2. Click Turn Windows features on or off on the left panel.
  3. Ensure that .NET Framework 3.5 (includes .NET 2.0 and 3.0) and .NET Framework 4.8 Advanced Services are enabled.
  4. If they aren’t enabled, check the boxes and click OK.
  5. Windows will download necessary files. Restart your PC if prompted.

Why this matters: Missing or corrupted .NET components can cause Hyper-V to fail loading assemblies it depends on.

Alternative Method: Use Windows Update Troubleshooter

If you suspect the error is related to Windows Updates (which sometimes affect Hyper-V components), try running the Windows Update Troubleshooter:

  1. Go to Settings > System > Troubleshoot > Other troubleshooters.
  2. Find Windows Update and click Run.
  3. Follow the on-screen instructions to fix update-related issues.
  4. Restart your PC and check if the Hyper-V error persists.

Frequently Asked Questions (FAQs)

What causes the Hyper-V Assembly Not Found error?

This error usually happens due to missing or corrupted Hyper-V files, incomplete installation, system file corruption, or incompatible Windows editions.

Can I use Hyper-V on Windows 11 Home?

By default, Hyper-V is not available on Windows 11 Home edition. You would need to upgrade to Windows 11 Pro or use third-party virtualization tools.

Do I need to enable virtualization in BIOS for Hyper-V?

Yes, virtualization (Intel VT-x or AMD-V) must be enabled in BIOS/UEFI for Hyper-V to function properly.

Will reinstalling Hyper-V delete my virtual machines?

No, your virtual machine files are stored separately and won’t be deleted by reinstalling Hyper-V. However, it’s always good to back up important VMs.

What if the error persists after trying all steps?

The issue might be deeper, such as Windows corruption or hardware incompatibility. Consider contacting Microsoft Support or using system restore options.

When Nothing Works

If you have tried all the steps above and still face the “Assembly Not Found” error, here are your last options:

  • Use System Restore: Restore your computer to a point before the error started occurring.
  • Reset Windows 11: Perform a Windows reset while keeping your files to fix deeper system issues.
  • Contact Microsoft Support: Visit the official Microsoft support website for advanced help and troubleshooting.
  • Visit Microsoft Tech Community: Engage with experts and other users facing similar issues at techcommunity.microsoft.com.

Conclusion

The “Hyper-V Assembly Not Found” error on Windows 11 can be frustrating but is usually fixable through simple steps. Starting from enabling Hyper-V correctly, repairing system files, reinstalling Hyper-V, and ensuring .NET Framework components are present covers most causes.

Always ensure your Windows version and hardware support virtualization. If problems persist, advanced options like system restore or contacting Microsoft are recommended.

By following this guide carefully, you should be able to resolve the error and enjoy using Hyper-V for your virtualization needs again.

Leave a Reply