Windows 11 Deployment – Using MDT 8456 with Windows ADK 26H1 (Build 28000)

Since Microsoft doesn't officially support Windows 11 Deployments with MDT, nor support any Windows ADK version newer than Windows ADK for Windows 10, version 1809 (build 17763), it's up to the OSD community to make it work. On the good side, with millions of MDT downloads during the years, you're not exactly alone 🙂 For this guide, I deployed Windows 11 Enterprise x64 25H2, but older Windows 11 versions, as well as Windows Server 2019/2022/2025, work too. Due to the bad quality of this ADK, this post is more of a educational guide (see the warning below).

Warning: Unfortunately, the driver support in WinPE x64 26H1 (28000) is broken, and even if you inject the correct driver, it will fail unless you load it specifically via drvload.exe (which works). Historically, Microsoft has done a terrible job testing new versions of the Windows ADK, and this might be the worst release yet. In general, you're better off using the 22H2 or 24H2 versions for your deployment.

For example, even the latest 25H2 driver for a Realtek 8168 NIC will fail to load unless explicitly loaded via a userexit script in bootstrap.ini. Put it this way, there is a reason the ConfigMgr (SCCM) team explicitly states they will not support ADK 26H1…

Real World Note: While the release notes for Windows ADK 26H1 (Build 28000) state it's only for Windows on ARM, this Windows ADK version also includes deployment tools and WinPE for Windows x64.

Food for thought

As of this writing, the only supported deployment solution for Windows 11 from Microsoft is ConfigMgr. If you don't mind a few tweaks, you can absolutely make MDT work for Windows 11, and even use the latest Windows ADK (Windows ADK for Windows 11 26H1).

Fun fact: You can deploy Windows 11 just fine with an older ADK version, too, but you will find that the native driver and chipset support is not the best. I recommend using at least Windows ADK for Windows 11 22H2 (Build 22621).

Issue #1 – WinPE x86 is Missing

The fact that Microsoft no longer includes the 32-bit (x86) version of WinPE is not exactly new, it was removed already in Windows ADK for Windows 11 22H2 (Build 22621), but MDT expects to find an x86\WinPE_OCs folder structure in the Windows ADK installation folder. If MDT can't find that, the console crashes with an exception:

System.IO.DirectoryNotFoundException. Could not find a part of the path 'C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Windows Preinstallation Environment\x86\WinPE_OCs'.

Solution

There are two steps needed for fixing this:

1. Create an empty x86\WinPE_OCs folder structure
2. Configure your deployment share(s) to prevent the creation of x86 boot images

Step 1: Create an empty x86\WinPE_OCs folder structure in the Windows ADK folder. MDT doesn't care about the content; it just looks for the folder 🙂 Here is a PowerShell snippet.

$OCx86Path = "C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Windows Preinstallation Environment\x86\WinPE_OCs"
New-Item -Path $OCx86Path -ItemType Directory -Force

Step 2: Configure your deployment share(s) to prevent the creation of x86 boot images.

Issue #2 – Generating Catalog Files will Fail

If you try generating a catalog for a WIM image using the latest Windows ADK, MDT will crash with this lovely error message:

Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.ComponentStudio.ComponentPlatformInterface, Version=6.2.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified.

This is because new versions of the Windows ADK include architecture-specific versions of Windows System Image Manager (WSIM). Versions earlier than 24H2 (26100) only had x86 versions.

Solution: Edit the C:\Program Files\Microsoft Deployment Toolkit\Bin\DeploymentTools.xml file and provide the %RealPlatform% value for the imgmgr.exe tool. Below is what the edited line should look like:

<tool name="imgmgr.exe">%ADKPath%\Deployment Tools\WSIM\%RealPlatform%</tool>

Extra tips!

Daniel Barras, thank you, shared some extra tips in the comments:

Tip #1. If using the Windows Update action, edit the C:\Program Files\Microsoft Deployment Toolkit\Templates\Distribution\Scripts\ZTIWindowsUpdate.wsf script, and replace verion with version.

Tip #2. Edit C:\Program Files\Microsoft Deployment Toolkit\Templates\Distribution\Scripts\ServerManager.xml and C:\Program Files\Microsoft Deployment Toolkit\Bin\ServerManager.xml

Find: <Role DisplayName='Fax Server' Id='DNS' />
Replace with: <Role DisplayName='Fax Server' Id='Fax' />

Find: <RoleService DisplayName='HTTP Errors' Id='Web-Http-Error' />
Replace with: <RoleService DisplayName='HTTP Errors' Id='Web-Http-Errors' />

Find: <RoleService DisplayName='WebDAV Publishing' Id='Web-DAV-Publishin' />
Replace with: <RoleService DisplayName='WebDAV Publishing' Id='Web-DAV-Publishing' />

Deploying Windows 11 25H2

The screenshots below show what it looks like deploying Windows 11 25H2 x64 using MDT 8456 and Windows ADK 26H1 (Build 28000).

Friendly tip: If setting up MDT for the first time, don't forget to include the updated Microsoft.BDD.Utility.dll (KB4564442), and to relax the deployment share permissions as described in this post: Fixing MDT deployment share permissions using PowerShell