|I would probably try a repair on the pst folder ...|
You will have to navigate all the way to C:\Program Files\Microsoft Office\Office14 folder and search for SCANPST.EXE file.
Confirm your mail account setup too. Make sure that you have everything correct including your password for logging on to the mail server.
Double click and follow it through for the repair. If that doesn't work, pop back here and reply to your message. There are others around besides me too. :)
I'm still learning everyday.