If you have problems with GPOs you can do a diagnostic using the debbug option with the following registry key:
1. Make sure that you have the folder %windir%\debug\usermode, if the usermode folder is not there, then manually create it.
2. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion
3. On the Edit menu, point to New, and then click Key.
4. Type Diagnostics, and then press ENTER.
5. Right-click the Diagnostics subkey, point to New, and then click DWORD Value.
6. Type GPSvcDebugLevel, and then press ENTER.
7. Right-click GPSvcDebugLevel, and then click Modify.
8. In the Value data box, type 30002 (as hex), and then click OK.
9. Exit Registry Editor.
10. At a command prompt, type the following command, and then press ENTER: gpupdate /force
11. . View the Gpsvc.log file in the following folder: %windir%\debug\usermode
Also, you can set GPP tracing with the following policy:
Computer Configuration\Policies\Administrative Templates\System\Group Policy\Logging and Tracing\Configure Shortcuts preference logging and tracing
When configured, the log file will be created in: