Boot from VHDX for Windows 8.1 Update

You may have seen my previous blogs on how to very quickly make your computer multi-boot into another operating system.

Now that Windows 8.1 Update and Windows Server 2012 R2 Update has been released, I’ll briefly repeat the steps.

  1. Download Convert-WindowsImage.ps1 and copy it to a temporary directory
  2. Start Windows PowerShell ISE in Administrator mode
  3. Run it with .\Convert-WindowsImage.ps1 -ShowUI
  4. Choose the required ISO file
  5. Choose the SKU
  6. Choose the VHD/VHDX Format, Type and Size
  7. Modify the Working Directory if necessary
  8. Type a name for the VHDX
  9. Optionally add an existing Unattend.xml file for further customization
  10. Hit Make the VHD!

You will see

My Windows 8.1 Enterprise VHDX was only 7.6GB small which came as a pleasant surprise.

The VHDX should still be mounted under a drive letter. If not, right-click the VHDX and mount it.
In my case I had ejected the mounted disks and manually re-mounted under drive F:

The following steps are needed to make your computer boot from the VHDX file:

  1. Open an administrative command prompt via WIN+X Command Prompt (Admin)
  2. Type bcdboot F:\Windows
  3. Type bcdedit /v to see the result in the Windows Boot Loader section

Taking the identifier you can change the description in your bootlist by typing:

bcdedit /set {545a3023-1918-11e2-bed1-bd8926e5c774} description “Windows 8.1 Enterprise with Update”

If you had configured Hyper-V on your Windows 8.1 computer, don’t forget to enable the hypervisor launchtype:

bcdedit /set hypervisorlaunchtype auto


  1. Wayne Wisniewski Wayne Wisniewski
    April 24, 2015    

    Every time I try to build my VHDX I receive the following error:
    “ERROR : There is a mismatch between the VHDPath file extension (), and the VHDFormat (.VHD). Please ensure that these match and try again.”
    Can you explain what I need to do?

    • Allan C Allan C
      May 17, 2015    

      I received that same error, but the only thing you need to do to fix it is add .vhdx to the name you are using.
      I was using “Win 10 10074 Bootable”, and the correction was “Win 10 10071 Bootable.vhdx”

      The script did work and finish after about 10 minutes, but I cannot boot yet from that vhdx.

    • May 28, 2015    

      Hi Wayne, the script does not work properly with Windows 10 and Server Technical Preview.
      You could try using the .WIM file:
      .\Convert-WindowsImage.ps1 -SourcePath ..\Source\WindowsServer2012R2\sources\install.wim -VHDPath .\WS2012R2DCu3_mbr.vhdx -VHDFormat VHDX -VHDPartitionStyle MBR -RemoteDesktopEnable -Edition ServerDatacenter
      .\Convert-WindowsImage.ps1 -SourcePath ..\Source\WindowsServer2012R2\sources\install.wim -VHDPath .\WS2012R2DCu3_gpt.vhdx -VHDFormat VHDX -VHDPartitionStyle GPT -RemoteDesktopEnable -Edition ServerDatacenter

      Cheers, Hans

No Pings Yet

  1. Boot from VHDX for Windows 8.1 Update | hyper-v... on April 4, 2014 at 18:45
  2. Maak een VHD met Windows | Eric's Tech Blog on May 29, 2015 at 17:28

Leave a Reply

Your email address will not be published. Required fields are marked *

Our Sponsors

Powered by