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Managing The Local Administrator Password - Part 3 - The Implementation

In this post I outline a step by step guide on implementing the solution. This post builds on the previous one.

This is mostly a condensed version of the author’s documentation with addition of some items that either I found unclear or were not covered by the author. 

In any case you should read the full documentation found here:

WARNING: The solution requires schema extension and this should never be taken lightly so do test properly and proceed at your own risk. 

The steps described in this section can be carried out on a Domain Controller or a management workstation. 

1. Install the CSE including the “Management Tools”

This installs: 

  • PowerShell module 
  • GPO templates (AdmPwd.admx and .adml) 

Note: I tested this on a domain with a local GPO store. If you are using a Central Store you should check if the templates have been copied. 

The following to steps are required for Windows 2008 and 7. Windows 2012 comes with .Net4 installed and enabled.

A) Download and install .Net4:

B) Configure PowerShell to load .Net4: 

Create a file named  “PowerShell.exe.config” in “\windows\system32\WindowsPowerShell\v1.0\” with the following content:

<?xml version="1.0"?>
    <startup useLegacyV2RuntimeActivationPolicy="true">
        <supportedRuntime version="v4.0.30319"/>
        <supportedRuntime version="v2.0.50727"/>


4. Update schema

PS C:> Import-module
PS C:> Update-AdmPwdSchema 

5. Remove “All Extended Rights” permission

This permission is not granted by default, you should however ensure it has not been granted manually as this would give access to the stored passwords.  

  • Use ADSIEDIT.msc to and connect to the “Default Naming Context”
  • Right-click the OU that will contain computer objects you want to manage,
  • Go to “Permissions” tab and click “Advanced”. 

You should also ensure that permission inheritance is enabled on sub-OUs.

6. Add Write permission to ms-MCS-AdmPwdExpirationTime and ms-MCS-AdmPwd attributes to SELF

PS C:> Set-AdmPwdComputerSelfPermission -OrgUnit

7. Add CONTROL_ACCESS permission to ms-MCS-AdmPwd attribute

In this step we grant permission to retrieve passwords from AD. See the previous post for more details. Firstly you need to create a group which you will use to grant access to retrieve passwords.

PS C:> Set-AdmPwdReadPasswordPermission -OrgUnit -AllowedPrincipals

8. Add Write permission to ms-MCS-AdmPwdExpirationTime attribute

In this step we grant permission to force password reset . 

PS C:> Set-AdmPwdResetPasswordPermission -OrgUnit -AllowedPrincipals

9. Create a GPO that will be used to enable password management

The GPO needs to be linked to the OU containing accounts of the computers you want to manager. You don’t configure any settings in the GPO. The magic happens in the next step. 

10. Register the CSE with the GPO

PS C:>  Register-AdmPwdWithGPO -GpoIdentity:

The cmdlet accepts displayName, GUID or DN.

This is all configuration that's required server side.

Now we need to deploy the CSE to computers we want to manage, and configure password requirements (see the previous post for and the documentation for details). 


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