When Office 365 accounts are first set up, users are prompted to select a time zone. This step is often missed and some users end up with the wrong time zone, usually Reykjavik/Monrovia (the default). This is easily fixed.

Change the time zone to the correct setting in Outlook Web App

1. Sign in to Outlook Web App, click Settings (), and then click View all Outlook settings at the bottom of the settings panel. (If you are using an older version, click on Mail under App Settings)
2. In the Settings window, click General, and then click Language and Time. (Region and time zone in older version.)
3. In the Current time zone box, click the arrow, and then click the correct time zone setting.
4. Click Save.