more than likely its software related.. try uninstalling the game again, and make sure you reboot and there's nothing left of the game after you turn back on the pc... mainly delete and of the directory left from the game after uninstall.

when you reinstall the game make sure that you reboot after you reinstall.. log back on, and test the game without updating it.. if it doesnt work, try using the latest update only.. which i guess is 1.5