I have a Windows Server 2008 x64 Standard with a 3.5 TB RAID 5. The system periodically hangs and I am unable to shutdown or restart. Task Manager only opens in the taskbar. When I finally seem to get a shutdown command to run, the server just sits with the hourglass flashing. This is happening right now, I am waiting for the server to shutdown. Any thoughts on what could be causing this and how to fix?