I have recently bought portal 2 during the steam sale and, after playing until after the old sector of Aperture, I took a week long break from the game. Now I come back, and every time I try to launch the game my screen turns black for a half second or so, and then it goes back to the desktop with the steam window having moved to the bottom right hand corner of the screen. No error messages ever appear, and I have tried verifying the cache, reinstalling the game, restarting my computer and updating my drivers, which, according to Microsoft, are up to date. Does any one have any experience with these sort of problems?
edit: I just tried L4D2 as well and it has the same problem. I also noticed that a button leading to my laptop's default graphics card's settings window shows up when I try to launch Is it possible my computer is suddenly trying to use the wrong card ( the default Lenovo card instead of the GTX 660m) when I launch? What could have caused that sudden change?