Set - MachineIdentityIsolation

Summary

Use this script to identify and remediate domain trust failures caused by Machine Identity Isolation (MII) enforcement after the September 2026 Windows 11 updates. It never restarts the device.

Affected devices can show: The trust relationship between this workstation and the primary domain failed.

Sample Run

Dependencies

• Set - MachineIdentityIsolation

Parameters

Parameter	Required	Default	Type	Description
Action	No	Status	String	Choose Status, Disable, or Repair.
domainUser	For Repair		PSCredential	Domain User name used to reset the computer account secure channel.
domainPassword	For Repair		PSCredential	Domain password used to reset the computer account secure channel.

Implementation

1. Export the agent procedure from ProVal's VSA RMM instance.
   Name: Set - MachineIdentityIsolation

   The export will download the necessary XML file.

2. Import this XML file into the partner's VSA RMM instance.

3. Export the Set-MachineIdentityIsolation-KI.ps1 from the ProVal's Internal VSA. This is also placed under the below path:
   Manage Files > Shared Files > PVAL > Set-MachineIdentityIsolation-KI.ps1

4. Map the Set-MachineIdentityIsolation-KI.ps1 into the 28th step of the script in the client's environment.

Output

Agent Procedure Log C:\ProgramData_Automation\Script\Set-MachineIdentityIsolation\Set-MachineIdentityIsolation-log.txt

Changelog

2026-09-22

• Initial version of the document