XSD schema for autounattend.xml

Microsoft's „Windows System Image Manager“ (WSIM) is used to create autounattend.xml files, and can also validate these files against an XSD schema:

Unfortunately, the XSD schema is not easily accessible, but it can be extracted from WSIM:

Using dotPeek

  1. Install the Windows ADK. You only need the „Deployment Tools“ feature, which includes WSIM.
  2. Run a .NET decompiler such as JetBrains dotPeek and open the file %ProgramFiles(x86)%\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\WSIM\microsoft.componentstudio.componentplatforminterface.dll.
  3. Navigate to the Microsoft.ComponentStudio.ComponentPlatformInterface.MyResources.resources resource and open it.
  4. Search for unattend to find the Base64 encoded schema:
  5. Select the entire Base64 encoded string (i.e. everything between <value> and </value>), copy it to the clipboard and decode it with PowerShell:
    [System.Text.Encoding]::ASCII.GetString( [System.Convert]::FromBase64String( (Get-Clipboard -Raw) ) ) | Set-Clipboard
    
  6. Your clipboard now contains the schema:
    <?xml version="1.0" encoding="ASCII"?>
    <xsd:schema targetNamespace="urn:schemas-microsoft-com:unattend" xmlns="urn:schemas-microsoft-com:unattend"
                xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                elementFormDefault="qualified" attributeFormDefault="unqualified">…

Using ildasm.exe

  1. If ildasm.exe is not already installed, download and install the .NET Framework 4.7.2 Developer Pack.
  2. Extract the resources embedded in microsoft.componentstudio.componentplatforminterface.dll:
    c:\>"%ProgramFiles%\Microsoft SDKs\Windows\v10.0A\bin\NETFX 4.7.2 Tools\ildasm.exe" "%ProgramFiles(x86)%\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools\WSIM\microsoft.componentstudio.componentplatforminterface.dll" /Output:"%USERPROFILE%\Desktop\Out.il"
    
  3. Open the file Microsoft.ComponentStudio.ComponentPlatformInterface.MyResources.resources, that was created on your desktop, using a text editor.
  4. Search for <?xml version="1.0" encoding="ASCII"?> to find the schema source code.