Reboot your computer, click Start, Shutdown, Restart
Make sure that Outlook does not display Offline in the bottom right hand side of the Oulook window.
Make sure your computer is physically connected to the network.
As a test open Firefox and Internet Explorer and go to Google and search something to make sure you can get to the web.
If you have completed these steps and you are still having issues please fill out a service request. If your PC is unable to access the internet use a PC near you.