Rocksmith crashes

Whenever i try to Open RS 2014 it Just closes when the Whitescreen with the rs pick in the bottom right Shows up. I tryed it without cables attached to my pc, updating my drivers, search for Problems in my Files via steam, rebooting but nothing i tried works. This came from one day to the other - was Playing rs Just fine the otherday And one night later CRASH. Anyone else has this Problem or know what to so?