Hi,
It seems some files are corrupt. Could you create GPO on another DC or using RSAT to create GPO on a client system?
Please try the use Process Monitor to trace the process on problematic DC for research.
http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx
Download and run it. Click File menu, check Capture Events, try to reproduce this error, when the error occurs, uncheck Capture Events again. Exported events to Logfile.PML and upload the file and then use Windows Live SkyDrive (http://www.skydrive.live.com/) to upload the file and then give us the download address.
Please also enable the GPMC log and upload the log file for research.
Enable Logging for Group Policy Management Console
http://technet.microsoft.com/en-us/library/cc737379(WS.10).aspx
Thanks.
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