For the past 2 weeks or more I've tried to figure out why my boss's calendar appointments were showing up with the wrong time.  Everything was 1 or 2 hours off.

I just looked at Outlook.com and noticed that it had been set to Pacific Time (we are on Central Time).  So I changed that, but all appointments are still showing the old time.  How can I get all of the appointment to change to the correct time without having to change each one manually?