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Boot Loader Did Not Load in Hyper-V VM

Ralph Burton 20 Reputation points
2025-09-09T00:23:06.0733333+00:00

I am using Hyper-V in Windows 11. I have very little experience with VMs, so treat me like I'm a 7-year-old.

I've been using a USB drive in a virtual machine. I've been following the operation where I start the VM, open disk management on the host machine, take the USB drive offline on the host machine, then open the settings on the VM, click on SCSI Controller, select "hard drive", click on Add, select the physical hard disk (USB drive), click apply, then "connect" on the VM.

This has been working just fine, until now.

When I try to start the VM, I get the following error message:

An error occurred while attempting to start the selected virtual machine(s)

Checkpoint operation failed

production checkpoints cannot be created

Cannot take checkpoint

checkpoint operation for 'VM_01' failed

Production checkpoints cannot be created for 'VM_01'

Cannot take checkpoint for 'VM_01' because one or more pass-through disks are attached.

When I open settings, then SCSI Controller, I do not see another hard disk, other than the hard disk for the boot, and the (standard) DVD entry.

I tried rebooting the host system. That didn't do any good.

I tried to disable checkpoints, then start the VM. It starts. I then try to connect, and I get a window that says:

Microsoft Hyper-V UEFI

Virtual Machine Boot Summary

  1. Unknown Device The boot loader did not load an operating system.
  2. SCSI DVD (0,1) The boot loader failed.
  3. Network Adapter A boot image was not found. [NOTE: I turned the network adapter off, so that is to be expected.]
  4. SCSI Disk (0,2) The boot loader did not load an operating system.

No operating system was loaded. Your virtual machine may be configured incorrectly.

Exit and reconfigure your VM or click restart to retry the current boot sequence again.

[BUTTON> Restart now]

I click on "restart now", and it goes into the Windows installation sequence (which I would rather not do).

So, my next thought was to roll back to a previous checkpoint.

I did some research on that, and found something using PowerShell. I opened PowerShell in Admin, and entered the following command:

Get-VMCheckpoint -VMName "VM_01"

Nothing is listed.

I see now that I was supposed to set the checkpoints manually and didn't. I was under the impression that it was done automatically. My bad.

I get the impression that the VM has an internal entry of some kind for a USB device that is not actually attached, but is not showing up in settings.

I have been stuck on this all day, and I very much hope that there is someone who has a very simple solution to this that I am completely unaware of and can clue me in before I jack around and make this situation worse.

If nothing else, is there a way to do a repair install on the VM?

I am dreading the prospect of having to rebuild the VM from scratch.

Any assistance with this would be appreciated.

Thanks!

Windows for business | Windows Client for IT Pros | Storage high availability | Virtualization and Hyper-V
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  1. Lychee-Ng 18,525 Reputation points Microsoft External Staff Moderator
    2025-09-09T08:35:47.4166667+00:00

    Hello Ralph Burton,

    Welcome to Microsoft Q&A!

    Don't worry, you did a great job diagnosing the problem. And you are right in your guess: the Virtual Machine probably thinks the USB hard drive is still attached, even though it's not showing up in the settings. This is a classic Hyper-V quirk that trips up everyone, not just beginners! And we can likely fix this without rebuilding the VM from scratch. There are two ways to go about this:

    Solution 1 - Edit the VM's configuration file:

    1. Turn off the VM completely in Hyper-V Manager
    2. Right-click on VM_01 (your virtual machine) > Settings
    3. Navigate to Hardware/Management > Configuration file
    4. Save the path to your VM .xml file > open with File Explorer
    5. Right-click the .xml file > Open with > Notepad
    6. Inside the file, there are several blocks formatted <driveX> … </driveX> (X is a number)
    7. Ctrl + F > <passthrough> > delete the whole block with that highlighted phrase. Example:
      1. If there's a block <drive2> … <passthrough> … </drive2>
      2. You select from <drive2> to </drive2> and press Delete
    8. Click File > Save > Go back to Hyper-V Manager > Start VM_01

    Solution 2 - Remove the ghost pass-through disk

    1. Disable Checkpoints in Hyper-V Manager (as you previously tried) and shut down VM
    2. In Settings > check SCSI Controller and IDE Controller for any extra hard disk entries.
    3. Open PowerShell as Administrator > Run Get-VM "VM_01" | Get-VMHardDiskDrive
    4. If you see PhysicalHardDisk or PhysicalDrive# > note the location details e.g. (0,1)
    5. Run Remove-VMHardDiskDrive -VMName "VM_01" -ControllerType SCSI -ControllerNumber 0 -ControllerLocation 1
      1. Replace 0 and 1 with the actual location details you noted from Run Get-VM command.
    6. In Settings > Firmware, ensure your main VHDX is at the top of the boot order.
    7. If it’s missing, go to SCSI Controller > Hard Drive > Add
    8. Select your existing VHDX > Apply changes > start the VM.

    Additional suggestion to prevent this in the future: If you are still content with using USB for passing through, always Safely Remove the USB from the VM before you shut it down and take it offline on the host machine.

    The above suggestions should get you back up and running quickly. If the issue persists or new errors appear, please consider sharing a screenshot of the PowerShell output from step 2 or the exact boot error. This will help us better understand the situation and provide a more accurate solution. If there is anything not clear or you need help doing the repair install, please do not hesitate to let me know!

    If the answer is helpful, please click "Accept Answer" and kindly upvote it to assist others who might face similar issues. If you have extra questions, please click "Comment".

    Note: To enable e-mail notifications, follow the steps in our documentation!

    1 person found this answer helpful.
  2. Quinnie Quoc 10,235 Reputation points Independent Advisor
    2025-09-09T08:19:53.6766667+00:00

    Hi Ralph Burton,

    Thank you for reaching out and providing detailed context—it's incredibly helpful. Based on your description, the issue appears to stem from the use of a pass-through USB disk, which disables production checkpoints in Hyper-V. This is expected behavior, as production checkpoints are not supported when a physical disk is attached directly to the VM.

    Since the VM is now failing to boot and no checkpoints are available, we recommend the following steps:

    Remove the USB disk from the VM configuration and ensure it's online again in the host’s Disk Management.

    Verify that the VM’s boot disk is still correctly attached and listed under the SCSI Controller.

    If the VM still fails to boot, you may attempt a repair install by booting from a Windows ISO and selecting the “Repair your computer” option.

    To avoid future issues, consider using Enhanced Session Mode or Remote Desktop USB redirection instead of pass-through disks.

    We understand how frustrating this can be, especially when you're just getting started with virtual machines. Please let us know if you'd like step-by-step help with the repair process or reconfiguring the VM safely.

    Best regards,

    Quinnie Quoc.

    1 person found this answer helpful.

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