ANSWER:

In order to change default behaviour for new accounts, you need to edit the Default User profile. However, this is not

HKU.DEFAULT

As this is the hive for the Local System user account, despite its confusing name. (MSDN Reference)

To edit the Default User Profile, you need to change the NTUSER.DAT from the Default profile directory (Location varies – C:Documents and SettingsDefault or C:UsersDefault etc)

You can do this by using the Registry Editor as follows:

• Run regedit
• Click on the HKEY_USERS hive
• Goto File -> Load Hive
• Select the NTUSER.DAT from the relevant directory
• Choose a Key Name (NB: This has no bearing on anything, it’s purely a way to reference the hive while it’s open.)
• Expend your new hive and make any changes needed
• Select the root of your new hive Goto File -> Unload Hive (This is important, as the file remains locked otherwise)

This NTUSER.DAT now gets copied to new profiles, and they in turn get all of the settings.

by Dan from http://serverfault.com/questions/389642