Almost if not all of my applications won't run. The shortcut buttons on my keyboard (Volume, Eject, Play) don't do anything. The computer won't shut down. Right now the only apps I can get to run are Finder and Chrome, nothing else. I can't run Activity Monitor, Terminal or Console to see what the problem is. This is like the third time it happens. I just manually shut down the computer. When I turn it on again, everything is working fine. This usually happens when I have my iMac on for about 2-3 days. Most of the apps simply stop working and I can't shut it down. Does anyone have any idea what the cause of this could be? Maybe give me a suggestion before I turn it off manually again... It pains me every time I have to do this.