outlook won't let computer shut down

Hi, when I try to shut down my MacBook Air it says I need to close outlook first. There is a permanent outlook screen that says "Weclome to office for Mac 2011" asking me to enter product key, set up etc. I use all the other programs but have no need to use outlook and I don't have the boxes allowing me to close the screen. When I quit the application it doesn't go anywhere. My computer now won't shut down and as I need to install updates for unrelated software, I can't because the computer won't restart. Can anyone help?