ADMX files

Using Administrative Templates in Group Policy you can change lots of the default Windows settings, like the Desktop, the Start Menu, Windows Explorer, ...
The settings that can be altered are described in .adm files. One of the benefits of these .adm files is that they can be adjusted. By modifying an .adm file, an administrator can manage almost every registry setting using a friendly interface and deploy these settings using Group Policy.

But there are a few disadvantages as well.

1. .adm files are stored in individual GPOs.
   For organizations with lots of GPOs, this means that every policy has a copy of every .adm file used in the policy. And these policies, including the .adm files are replicated to all domain controllers in the environment. If you know that the .adm files take about 4 Mb of a policy's size, you can do your own math.
2. .adm files are added in a specific language.
   This can be annoying in an environment where administrators speak different languages and would like to see the templates in their own language.

Vista and Longhorn Server introduce a new format for registry-based policy settings: ADMX files (in XML format) to address these issues.

ADMX files are divided into language-neutral and language-specific resources, available to all Group Policy administrators. These factors allow Group Policy tools to adjust their UI according to the administrator's configured language. Adding a new language to a set of policy definitions is achieved by ensuring that the language-specific resource file is available.

File Type	File Location
ADM	C:\inf
ADMX language neutral	C:\policydefinitions
ADMX language specific	C:\policydefinitions\en-us  for the US English ADMX language

One of the main benefits of using the new ADMX files is the central store. This option is available when you are managing domain-based GPOs, although the central store is not used by default.
In Vista and Longhorn the GPO Editor will no longer copy the adm files to each edited GPO, but will provide the ability to read from either a single domain-level location on the domain controller's Sysvol or from the local administrative workstation when the central store is unavailable.

1. To create the central store:
   1. Create the root folder for the central store:
      C:\Sysvol\domain\policies\PolicyDefinitions on your DC
   2. Create a subfolder in the central store for each language your Group Policy administrators will use. Each subfolder is named after the appropriate ISO-style Language/Culture name. For example, to create a subfolder for US English:
      C:\Sysvol\domain\policies\PolicyDefinitions\en-us

 

1. Populate the central store:
   1. Copy all the language-neutral ADMX files from your Vista workstation to the central store on your DC using the xcopy command:
      xcopy c:\PolicyDefinitions\*
      %logonserver%\sysvol\%userdnsdomain%\policies\PolicyDefinitions
   2. Copy all the ADMX language resource files from your Vista workstation to the central store on your DC:
      xcopy C:\PolicyDefinitions\en-us\*
      %logonserver%\sysvol\%userdnsdomain%\policies\PolicyDefinitions\en-us

Important factors:

• New Vista or Longhorn-based policy settings can only be managed from Vista or Longhorn-based computers. These policies are defined only in ADMX files and, as such, are not exposed on the Windows Server 2003, XP or 2000 versions of the group policy management tools.
• The Vista and Longhorn version of the GPMC can be used to manage all OS systems that support Group Policy.
• In the majority of situations, you will not notice the presence of ADMX files during your day-to-day Group Policy administration tasks.