How to stop Mountain Lion to stop shutting down and closing all my applications? I tried to look up related problems with this, but I haven't been able to find a solution. After leaving my computer on, charged, and step away, sometimes it logs my account off. When I come back, log on, all my applications have been turned off. I have adjusted the settings under "Energy Saver" and allow the computer a longer sleep time, but that doesn't seem to work. 

OS X Version 10.8.2
Any suggestions?
When you say it "logs your account off" do you mean that you have to enter your password?

My guess is that someone has set Security &amp; Privacy settings to require a login password after sleep or screen saver begins. Go to Apple menu > System Preferences, click Security &amp; Privacy, and then click General to see.