To modify the registry via group policy.

  1. Open the Group Policy Management Console . Right-click the Group Policy object (GPO) that should contain the new preference item, and then click Edit .
  2. In the console tree under Computer Configuration or User Configuration , expand the Preferences folder, and then expand the Windows Settings folder.
  3. Right-click the Registry node, point to New , and select Registry Item .
  4. In the New Registry Item dialog box, select an Action for Group Policy to perform. (For more information, see “Actions” in this topic.)
  5. Enter registry settings for Group Policy to configure or remove. (For more information, see “Registry settings” in this topic.)
  6. Click the Common tab, configure any options, and then type your comments in the Description box. (For more information, see Configure Common Options.)
  7. Click OK . The new preference item appears in the details pane.

 

Actions

This type of preference item provides a choice of four actions: Create , Replace , Update , and Delete . The behavior of the preference item varies with the action selected and whether the registry key or value already exists.

Create Create a new registry value or key for computers or users.
Delete Remove a registry value or a registry key and all of its values and subkeys for computers or users.
Replace Delete and recreate a registry value or key for computers or users. If the target is a registry value, the net result of the Replace action is to overwrite all existing settings associated with the registry value. If the target is a registry key, the net result is to delete all values and subkeys in the key, leaving only a default value name with no data. If the registry value or key does not exist, then the Replace action creates a new registry value or key.
Update Modify settings of an existing registry value or key for computers or users. This action differs from Replace in that it only updates settings defined within the preference item. All other settings remain as configured in the registry value or key. If the registry value or key does not exist, then the Update action creates a new registry value or key.

Note that if you want to rename a key, you have to delete it first, then create again. If it has subkeys, the deletion will delete the subkeys, but you have to create them one by one~

 

Refrences

https://technet.microsoft.com/en-us/library/cc753092(v=ws.11).aspx