Invoke-OSDeployMDT

Apply OSDeploy customizations at MDT LiteTouchPE exit stages.

Invoke-OSDeployMDT reads the MDT LiteTouchPE exit environment and applies OSDeploy customizations during Update Deployment Share. Install-OSDeployMDT registers the command in the deployment share template so MDT calls it at the WIM, POSTWIM, ISO, and POSTISO stages.

Requirements

Run this command through the MDT Update Deployment Share process on a host with MDT, the Windows ADK, the WinPE add-on, DISM, Windows PowerShell, PowerShell 7, and internet access for uncached tools and modules. The WIM stage also uses curl.exe, robocopy.exe, reg.exe, PowerShellGet, and Windows image servicing commands.

Initialize the deployment share first with Install-OSDeployMDT. See Microsoft MDT for the related setup.

Do not simulate an MDT stage against an arbitrary path. The function assumes that MDT supplied a valid mounted image or ISO build tree and does not validate every environment value before changing content.

The implemented WIM app and driver paths are amd64 oriented. AzCopy and curl download only amd64 payloads, 7-Zip copies only its x64 payload, OSDeploy driver selection reads boot-assets\winpedrivers-amd64, and driver log entries record amd64.

Parameters

Parameter	Type	Default	Accepted values and behavior
-SetInputLocale	String	en-us	Set the WinPE input locale passed to DISM. The function always sets all other international settings to en-us.
-SetTimeZone	String	Current timezone from tzutil /g	Use a timezone name present in tzutil /l. Validation occurs before stage handling.
-WhatIf	Common parameter	Not enabled	At WIM or POSTISO, skip that stage's customization body. Environment display, global build-context creation, the final delay, and an enabled exit prompt still occur.
-Confirm	Common parameter	Not enabled	At WIM or POSTISO, prompt before that stage's customization body. Other recognized or unrecognized nonempty stages have no confirmation boundary.

Examples

Display help outside MDT

Run the command without an MDT STAGE environment variable to return its help object without creating a build context or changing content:

Remove-Item Env:\STAGE -ErrorAction SilentlyContinue
Invoke-OSDeployMDT

Use the MDT-provided defaults

The exit command registered by Install-OSDeployMDT runs this invocation at each MDT stage. During WIM, it applies en-us international and input settings and uses the host's current timezone:

Invoke-OSDeployMDT

Set the WinPE keyboard and timezone

Use valid DISM locale and Windows timezone values when invoking the command from the MDT exit environment:

Invoke-OSDeployMDT `
	-SetInputLocale 'en-GB' `
	-SetTimeZone 'GMT Standard Time'

To make these values persistent, include the parameters in the Invoke-OSDeployMDT exit entry in DEPLOYROOT\Templates\LiteTouchPE.xml. Running Install-OSDeployMDT -Force later overwrites that template from the MDT installation before restoring only the default exit command.

Preview a WIM stage

Use -WhatIf when MDT has supplied the current WIM-stage environment. The function creates and leaves the global build context but skips the WIM customization body:

Invoke-OSDeployMDT -WhatIf

MDT Environment

When STAGE is absent or empty, the function runs Get-Help -Name Invoke-OSDeployMDT and returns immediately. With any nonempty value, it displays these MDT variables and replaces $global:BuildMedia with the current build context:

Variable	Use
STAGE	Selects stage behavior. Recognized values are WIM, POSTWIM, ISO, and POSTISO.
CONTENT	Becomes the mounted image path at WIM; at POSTISO, identifies the captured ISO used to derive the temporary ISO tree and output name.
ARCHITECTURE	Records the build architecture and selects cached app content. Current app and driver implementation is amd64 oriented.
DEPLOYROOT	Locates Boot\bootbins, template drivers, driver logs, and the patched ISO output.
INSTALLDIR	Locates MDT's Templates\BootOrder.txt for ISO creation.
ADKPath	Displayed for diagnostics. ADK tool paths are independently resolved from the Windows Kits registry or default installation path.
TEMPLATE	Displayed for diagnostics; it does not select a code branch.
TEMP	Stores DISM logs and temporary INF files.
ProgramData	Locates OSDeploy caches for PowerShell packages and WinPE apps, plus the unified Boot-Assets driver library.

For the normal MDT exit flow, CONTENT has these meanings:

Stage	CONTENT value	Implemented action
WIM	Mounted WinPE image directory	Apply WIM customizations.
POSTWIM	Captured WIM file	None.
ISO	ISO staging directory	None.
POSTISO	Captured ISO file	Patch the sibling temporary ISO tree and build a CA 2023 ISO.

An unrecognized nonempty STAGE also performs no stage-specific action. It still replaces $global:BuildMedia, waits 10 seconds, and can prompt on exit.

WIM Stage

At STAGE=WIM, CONTENT is the mounted WinPE root. One ShouldProcess call gates the complete WIM body.

Boot and ADK files

The function creates DEPLOYROOT\Boot\bootbins and copies available files into it:

• bootmgfw.efi and bootmgfw_EX.efi from the mounted image.
• efisys.bin, efisys_noprompt.bin, efisys_EX.bin, efisys_noprompt_EX.bin, and etfsboot.com from the ADK Oscdimg directory.

Missing boot files are skipped. It also copies oa3tool.exe from the ADK into Windows\System32 when that source exists.

WinPE settings and PowerShell support

DISM sets the timezone, sets all international settings to en-us, sets the requested input locale, and writes timestamped logs under the host's TEMP directory.

The PowerShell preparation step:

• Creates default-user, system-profile, module, script, and repository folders in the mounted image.
• Uses C:\ProgramData\OSDeployCore\cache\psrepository as a host cache for PackageManagement 1.4.8.1, PowerShellGet 2.2.5, and nuget.exe.
• Unregisters any existing OSDeployCore PowerShell repository, registers the cache under that trusted name, saves PackageManagement and PowerShellGet into WinPE, then unregisters it. The command therefore leaves no OSDeployCore repository registered in the host session.
• Creates WinPE PowerShell repository, profile, environment, and execution-policy content where needed.
• Loads and changes the mounted default-user registry hive and injects two temporary INF drivers for environment and execution-policy values.
• Saves the current OSDCloud module from the PowerShell Gallery into Program Files\WindowsPowerShell\Modules in the image.

These operations can download content and change host-side caches as well as the mounted image.

WinPE tools

When the corresponding executable is absent from mounted Windows\System32, the function uses C:\ProgramData\OSDeployCore\cache\winpe-apps to cache and copy:

• AzCopy v10 for Windows.
• The latest curl for Windows amd64 package.
• 7-Zip 26.00 x64 extra tools.

The 7-Zip step removes older cached 7-Zip versions. Existing executables in the mounted image cause their installer step to return without refreshing the cache.

WinPE drivers and logs

The function reads CONTENT\winpe-drivers.json when present. Invalid JSON warns and starts with an empty applied-driver list. When the mounted log is absent, the function resets the list and removes an existing DEPLOYROOT\Boot\winpe-drivers.json.

Driver selection then follows this order:

1. Enumerate each immediate subdirectory under DEPLOYROOT\Templates\winpe-drivers and apply it automatically with recursive, unsigned-driver servicing unless its folder name is already logged.
2. Enumerate unapplied immediate subdirectories under OSDeploy Core boot-assets\winpedrivers-amd64.
3. When OSDeploy Core drivers are available, open Out-GridView with multi-selection. Cancel the picker to skip these optional drivers.

Deduplication uses the driver folder Name, not the full path or file contents. Applied entries are written to CONTENT\winpe-drivers.json and copied to DEPLOYROOT\Boot\winpe-drivers.json. Add-WindowsDriver servicing objects can reach the success pipeline.

POSTISO Stage

At STAGE=POSTISO, one ShouldProcess call gates the complete patch-and-build body. The function uses the parent directory of CONTENT and its sibling ISO folder as the source tree. It derives the output base name from the captured ISO and writes:

DEPLOYROOT\Boot\<IsoBaseName>_uefi2023ca.iso

If DEPLOYROOT\Boot\bootbins\bootmgfw_EX.efi exists, it overwrites ISO\EFI\MICROSOFT\BOOT\bootmgfw.efi. If that source is missing, the function warns but continues to ISO creation.

When ADK oscdimg.exe exists, the function starts it and waits for it to finish. The boot definition uses MDT's Templates\BootOrder.txt, ADK etfsboot.com, and DEPLOYROOT\Boot\bootbins\efisys_EX.bin. The function does not inspect or return the oscdimg process exit code. A missing oscdimg.exe produces a warning and no patched ISO.

Prompts and Exit Behavior

The WIM OSDeploy Core driver picker appears only when unapplied Boot-Assets drivers exist. Canceling it skips those drivers and continues.

After every invocation with a nonempty STAGE, the function waits 10 seconds. If a truthy PauseOnExit variable is visible in caller scope, it then prompts Press Enter to continue; PauseOnExit is not a command parameter, and its displayed value does not control the fixed 10-second wait. Invocations without STAGE return before this delay and prompt.

WhatIf and Confirmation

ShouldProcess is implemented only for WIM and POSTISO:

• -WhatIf skips all work inside the matching stage body, including downloads, mounted-image changes, driver prompts, and ISO creation.
• -Confirm prompts once for the matching stage body.
• Both parameters act after environment display and $global:BuildMedia replacement and before the final delay or optional exit prompt.
• POSTWIM, ISO, and unrecognized nonempty stages do not call ShouldProcess because they currently have no stage-specific body.

Output

When STAGE is absent, the function returns the System.Management.Automation.HelpInfo object emitted by Get-Help.

The function has no single structured stage result. During WIM, Add-WindowsDriver can emit Microsoft.Dism.Commands.BasicDriverObject values, and delegated or native commands can emit incidental success-stream output. Host messages and $global:BuildMedia are not intentional pipeline results. POSTISO does not return the created ISO or its process exit code.

See the MDT invocation workflow, the Install-OSDeployMDT guide, or the Invoke-OSDeployMDT command reference.