The database for Outlook profile has been corrupted and there are chances that you have to build a new Outlook profile in Mac Outlook 2011.
Workaround Solution to Fix Mac Outlook Not Syncing With Exchange Server. So, keep reading till the end of the write-up. The post explains several methods to resolve Mac Outlook not syncing with Exchange Server.This opens a new window with all the meeting details. Right-click the day when you want to request a meeting and click the New Meeting Request or New Appointment depending on what type of event you want to add to your Outlook Calendar. Launch the Outlook app and switch to Calendar view using the small Calendar icon at the bottom-left corner.