1. ADMX Schema
The
rules of ADMX and ADML file creation and syntax usage are defined in
the ADMX schema. The schema is a set of three files that define the
elements and attributes, how the syntax is constructed, and how the
ADMX and ADML files are used in conjunction.
You can download the ADMX schema files from http://go.microsoft.com/fwlink/?LinkId=86094.
After downloading and installing the admxSchema.msi file, you will have
three additional files that you can use to help design new ADMX and
ADML files. These files, located at C:\Program Files\Microsoft Group
Policy\admxschema by default, include:
These
files can be used in conjunction with tools such as Microsoft Visual
Studio to help create custom ADMX and ADML files.
With
.adm templates, you have only two CLASS options: MACHINE and USER. If
you were to create a registry-based policy setting that could apply to
both the computer and user portions of the registry, you would have to
include two POLICY descriptions that were exactly the same, but locate
one in the CLASS MACHINE and one in the CLASS USER portions.
For
ADMX files, a third option was added to the attribute for a policy
setting. You can now write the policy setting once in the ADMX file and
define the classBoth, such as Class=Both.
This causes the GPME to display the policy setting in the exact same
location, placed under the Computer Configuration and User
Configuration sections. attribute to have a value of
The rest of the
operations will apply. If the administrator configures the setting
under Computer Configuration through the GPME, the policy setting will
be saved as configuring the HKLM portion of the registry; for User
Configuration, the configuration operation will cause the policy
setting to configure the HKCU portion of the registry.
2. ADMX File Structure
ADMX files create the category structure and policy settings within the GPME. The overall structure of an ADMX file is shown in Figure 1.
Table 1 explains the use of each section in the ADMX file.
Table 1. ADMX File Section Descriptions
| Section | Description |
|---|
| XML Declaration | Required to validate as an XML-based file. |
| policyDefinitions Element | Contains all other elements for the ADMX file. |
| policyNamespaces Element | Defines the unique namespace for this ADMX file. The policyNamespaces element also provides a mapping to external file namespaces if a reference to the category element is defined in a different ADMX file. |
| resources Element | Specifies the requirements for the language-specific resources; the minimum required version of the associated ADML file. |
| supportedOn Element | Specifies
references to localized text strings defining the operating systems or
applications affected by a specific policy setting. |
| categories Element | Specifies categories under which the policy setting in this ADMX file will be displayed in the GPME. |
| policies Element | Defines the individual policy settings in the GPME. |
3. ADML File Structure
The
ADML files are responsible for defining the language-specific text that
is shown in the GPME. These files are produced for each language that
will be supported within your company (one file per language). The
overall structure of the ADML file is shown in Figure 2.
Table 2 explains the use of each section in the ADML file.
Table 2. ADML File Section Descriptions
| Section | Description |
|---|
| XML declaration | Required to validate as an XML-based file. |
| policyDefinitionResources Element | Contains all other elements for the ADML file. |
| resources Element (.adml) | Contains a stringTable Element and a presentationTable Element for a specified language. |
Warning
A stringTable element and a presentationTable element must be defined in the ADML file in order, as required by the ADMX schema: stringTable element followed by presentationTable element. The parser for the Group Policy tools will present an error if the order of these two elements is reversed. |
