> For the complete documentation index, see [llms.txt](https://www.osdeploy.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.osdeploy.com/guide/cmdlets/install-osdeploysoftware/windows-adk-26h2.md).
# Windows ADK 26H2
Install Windows ADK 26H2 and its matching Windows PE add-on for OSDeploy boot-image creation.
Use the exact name `adk-26h2` to download or install Windows ADK `10.1.26100.9457` and its matching Windows PE add-on. These components provide the deployment and WinPE files used to create standard OSDeploy boot images.
{% hint style="info" %}
OSDeploy media, USB, and Core workflows accept ADK `10.1.26100.2454` or `10.1.26100.9457`, each with its matching Windows PE add-on. This component installs the current 26H2 kit, version `10.1.26100.9457`. The supported 25H2 kit, version `10.1.26100.2454`, also remains valid.
{% endhint %}
## Requirements
Run the command from an elevated PowerShell 7.6 or later MSI installation on Windows 11 25H2 build 26200 or later.
The command requires the current OSDeploy module, `curl.exe`, and internet access. It uses the ADK and WinPE setup URLs in current module metadata. The helper does not expose an architecture selector or branch on host architecture.
## Preview
Return the ADK setup URL, documentation links, and install command without creating cache directories, downloading setup programs, or inspecting installed ADK versions:
```powershell
Install-OSDeploySoftware -Name 'adk-26h2'
```
## Install
Download the setup programs and install the ADK when no Windows ADK is registered:
```powershell
Install-OSDeploySoftware -Name 'adk-26h2' -Force
```
When no ADK is detected, the helper creates offline layouts and silently installs these features:
* `OptionId.DeploymentTools`
* `OptionId.ImagingAndConfigurationDesigner`
* `OptionId.WindowsPreinstallationEnvironment` from the Windows PE add-on
The setup programs and offline layout content are retained under:
```
C:\ProgramData\OSDeployCore\software\Microsoft.WindowsADK_10.1.26100.9457\
```
The setup processes run quietly with CEIP disabled and `/norestart`. Any nonzero download, layout, ADK, or WinPE setup exit code stops the command.
{% hint style="info" %}
If any Windows ADK version is registered, the helper downloads the two setup programs but keeps the installed version and skips layout creation and installation. OSDeploy media, USB, and Core workflows accept only ADK `10.1.26100.2454` or `10.1.26100.9457`; another installed version does not satisfy those requirements. The helper still creates the missing x86 `WinPE_OCs` directory used by the MDT Windows PE MMC snap-in when needed.
{% endhint %}
## Download Only
Download the ADK and Windows PE setup programs without installing them:
```powershell
Install-OSDeploySoftware -Name 'adk-26h2' -DownloadOnly
```
This saves `adksetup.exe` under the `adk` subfolder and `adkwinpesetup.exe` under the `adkwinpe` subfolder. It does not create the complete offline layouts or apply the x86 workaround.
## WhatIf and Result
Add `-WhatIf` to `-Force` or `-DownloadOnly` to report the parent action without invoking the ADK helper. No cache directories or setup files are created in that mode.
A completed `-Force` action returns `Component` set to `Windows ADK 26H2` and `Status` set to `Installed`. A completed `-DownloadOnly` action sets `Status` to `Downloaded`. The parent result does not include setup paths, exit codes, detected ADK version, or whether installation was skipped. The setup commands do not request a restart.
## Verify
Confirm the registered ADK and Windows PE files:
```powershell
Get-ItemProperty `
'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*', `
'HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*' |
Where-Object DisplayName -Like 'Windows Assessment and Deployment Kit*' |
Select-Object DisplayName, DisplayVersion
Test-Path 'C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Windows Preinstallation Environment'
```
## Next Step
Install [7-Zip](/guide/cmdlets/install-osdeploysoftware/7-zip.md), then continue with [Build-OSDeployBoot](/guide/cmdlets/build-osdeployboot.md).
---
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