Microsoft just released a free tool to search for errors in Group Policy configuration - totally new and cool tool in the Best Practice Analyzer (BPA) series.
Download here:GPDBPA for Windows XPGPDBPA for Windows XP x64 EditionGPDBPA for Windows Server 2003GPDBPA for Windows Server 2003 x64 EditionRead more here:Microsoft KB 940122 article: "How to use the Microsoft Group Policy Diagnostic Best Practice Analyzer (GPDBPA) tool to collect and to analyze data"
Quote from KB article:You can use the Microsoft Group Policy Diagnostic Best Practice Analyzer (GPDBPA) tool to collect data about an environment's Group Policy configuration. For example, you can use this tool to analyze a Group Policy configuration for the following purposes:
• To search for common configuration errors
• To discover and to diagnose problems
• To collect data for archiving
The account that you use to run the tool must have the appropriate permissions to access both the Active Directory database on an environment's domain controllers and the SYSVOL file structure that is maintained on those domain controllers. Additionally, the account must have local Administrator permissions on the Group Policy client.
There are two additional prerequisites for using the GPDBPA tool:
•The Microsoft .NET Framework version 1.1 or a later version must be installed on the computer on which the GPDBPA tool is installed.
•The Windows Management Instrumentation (WMI) service must be running on the environment's domain controllers.