I don't know if this will help, but open an rlevated command prompt ( click start, in the search box type cmd, in the entry that appears right click the entry and select run as administrator) In the window that comes up, type ot copy/paste sfc /scannow and press enter. See if that will help. That is a system file checker that will scan only system files and attempt to replace any it finds missing or corrupted. But, If you have custom themes installed it will remove them.