Almost every time I shut down or restart my W7 Professional OS I get the message "1 program still needs to close: (Waiting for) Hidden_d3d window. This program is preventing Windows from shutting down." When I do a force close the OS goes ahead and shuts down. The next start-up is fine and all is well until it's time to shut down again - then same message.
I've seen some banter about Logitech Bluetooth mouse issues that cause a similar problem.