How do I configure unattended installation using Unattend.xml?
Applies to: Microsoft Deployment Toolkit (MDT) 8456 and later
Last updated: May 2025
Problem
You want to automate parts (or all) of the Windows installation process so users don’t need to manually interact with setup prompts during deployment.
Solution
MDT uses a file called Unattend.xml to automate the Windows Setup experience. You can configure this file per Task Sequence using the Windows System Image Manager (WSIM), or let MDT generate a basic one for you.
Step-by-Step Guide
1. Open the Task Sequence
- In Deployment Workbench, go to:
- Task Sequences > right-click your sequence > Properties
- Click the OS Info tab
- Click Edit Unattend.xml
This opens the WSIM editor. If prompted to create a catalog file, select Yes (this may take a few minutes).
2. Understand the XML Structure
The Unattend.xml file is divided into configuration passes. The most commonly used are:
| Pass | Description |
|---|---|
| 1 – windowsPE | Preinstallation setup (e.g., disk config) |
| 4 – specialize | System setup (e.g., computer name, domain) |
| 7 – oobeSystem | Final setup (e.g., user account creation) |
3. Common Unattended Settings
You can automate values such as:
- ProductKey
- ComputerName
- RegisteredOrganization
- TimeZone
- InputLocale
- JoinDomain
- SkipUserOOBE
- AutoLogon
Example – Setting TimeZone:
- Navigate to:
Microsoft-Windows-Shell-Setup>TimeZone - Enter value:
Pacific Standard Time
4. Save and Validate
- After making changes, File > Save the
Unattend.xml. - Close WSIM.
The file will be saved under:
php-templateCopyEdit<DeploymentShare>\Control\<TaskSequenceID>\Unattend.xml
5. Optional: Set Global Defaults via CustomSettings.ini
You can supplement Unattend.xml automation using:
CustomSettings.inifor deployment wizard defaultsBootstrap.inifor pre-deployment settings
This is ideal for managing automation across multiple Task Sequences.
Notes
- Always validate the XML after editing—invalid syntax will break deployment.
- Not all settings belong in every configuration pass; follow Microsoft’s WSIM documentation.
- Use a reference virtual machine or test PC for verifying changes before production.
