Since I installed ATI Tray Tools, some .exe couldn't be run anymore (eg. Adobe Flash Player installation, some executable from Catalyst Control Center, Starcraft II). The message I got was: "Blizzard Launcher has stopped working" (when trying to launch StarCraft II) After closing ATI Tray Tools, the problem was solved. I was using ATI Tray Tools for monitoring GPU temperature in the System Tray, but I uninstalled it now.