I am part of a team of IT Engineers who are currently revamping a large organisation.

The previous IT department had some Group Policy objects in place for installing software(s), applying security related changes to machines, etc, etc.

On some of the group policy objects, Loopback processing (Merge Mode) is enabled.. See below for an example :

enter image description here

enter image description here

As loopback processing isn't something you can just enable to assist one policy (In other words it's global), what affect will this have on the computers?

If I've understood correctly, merge mode will allow you to define computer policies and apply them to users? Or is it.. Allow user configurations to be applied to computers??

If merge mode will allow user configurations to be applied on a computer level, how will the example policy affect computers?


Loopback enables you to define USER group policies at the OU where the computer resides, and have the policies applied to any user that logs on to those computers. Normally, user policies are applied from the OU hierarchy where the user account resides.

We can't predict what the impact will be from changing Merge to Replace. You need to run the Group Policy Modeling Wizard, and create two reports. One that has loopback with Merge, and one that has loopback with Replace. Save the two reports and compare them.

Typically Replace is used to enforce user settings at the OU where the computer resides. Replace effectively ignores any settings in the user account OU structure. Merge is used if there are settings at the user account OU structure that would be necessary. You will need to examine the reports to determine what is best for your environment.

  • So basically, the way the gpo is currently configured:
    – Jake
    Sep 24 '15 at 14:05
  • So basically, taking into account of the way the gpo is currently configured: - If loopback:merge is enabled, any user configuration configured in a GPO which is in the computer's OU will be applied to any user who logs onto that machine?
    – Jake
    Sep 24 '15 at 14:14
  • With loopback enabled, any user setting at the computer GPO is applied, doesn't matter if it is Merge or Replace. "Merge" indicates that the user settings defined in the computer's Group Policy Objects and the user settings normally applied to the user are combined. If the settings conflict, the user settings in the computer's Group Policy Objects take precedence over the user's normal settings.
    – Greg Askew
    Sep 24 '15 at 14:18

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.