WMI filters are used to determine the scope of Group Policies based on computer attributes such as the operating system, free hard disk space or brand and model.
WMI filters only apply on Windows XP and Winsows Server 2003 computers. WMI filters are ignored on earlier versions of Windows. In order to be able to filter policies you will need at least one domain controller running Windows Server 2003 in your environment.
Download the GPMC SP1 from http://www.microsoft.com/windowsserver2003/gpmc/default.mspx.
Install the GPMC SP1 according to the setup instructions.
Once installed open the GPMC under Administrative Tools
Expand the domain under which you want to create a WMI Filter
Right-Click the WMI Filter object and select New…
Type in a Name and a friendly description for your new filter
The current namespace should be root\CIMv2; This is the most common namespace for WMI queries. All Win32_* classes are located.
In the Query textbox write your query.
Here is a query that would return true if the C: drive has at least 100MB free
Select * from Win32_LogicalDisk where FreeSpace > 104857600 AND Caption = "C:"
How to determine all of the Win32_* available classes and properties?
Download the WMI Tools available at http://www.microsoft.com/downloads/release.asp?releaseid=40804
Using the WMI Object browser you can search for classes and even see all the different properties.
Step Four: Assign a WMI Filter to a Group Policy
Select the Group Policy Object and in the right pane, in the WMI Filtering section click the drop down menu and select the WMI Filter you have just created.
The Group Policy will only be applied if the WMI Filter assigned returns true.
Group Policy Processing Stops After You Apply a WMI Filter to a GPO
http://support.microsoft.com/kb/814613/en-us WMI Filters overview
http://www.microsoft.com/technet/treeview/default.asp?url=/technet/prodtechnol/windowsserver2003/proddocs/entserver/wmifltr_default.asp Managing WMI security
http://www.microsoft.com/resources/documentation/WindowsServ/2003/enterprise/proddocs/en-us/wmi_managing_security.asp Windows Management Instrumentation (WMI)
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnanchor/html/anch_wmi.asp WMI Classes
The author is a Windows system administrator located in Montreal, Quebec; He can be reached at email@example.com