Method 1: Press and hold Option key when launching Outlook to rebuild the identity. Method 2: Press and hold Alt key (windows) and click the Outlook icon on on the Dock (If the icon not appears on dock, Go to /Applications/Microsoft Office 2011 folder and drag the outlook file to Dock). Microsoft database utility will appear.
Now click the Rebuild button. It will reboot Outlook database. After it finished the process, click the Done button and close the Microsoft Database utility. Method 3: Open Applications and choose Microsoft Office 2011 folder. Then select the office folder and find Microsoft Database Utility.app. Here you can find rebuild option. Solution 2:- (Remove Outlook preference file) Go to /Library/Preferences and delete Outlook preference file (file name starts with “com.microsoft”). Solution 3: (Nano suggested) Open Terminal app and type the following command to delete old preferences.
Defaults delete com.microsoft.Outlook Next type or paste the following command to kill the cached preferences. Killall cfprefsd Then launch Microsoft Outlook. If the above methods doesn’t work, re-install office 2011 software.
Note: The ability to manually repair or rebuild a database is not available in Outlook 2016 for Mac. If a problem such as Outlook data corruption occurs, Office 2016 for Mac automatically repairs and rebuilds the Office database for you. For more information, see About the Office 2016 for Mac database.