I am using Office 2016 by way of an Office 365 installation, and Outlook 2016 won’t open. It hangs up on Starting / Processing screen.
1) Click the Windows button or press the Windows key on your keyboard
2)In the Run box, type outlook.exe /safe
3) Click OK
4) When prompted to ‘Choose a Profile’, click OK (you may need to choose a profile if you have multiple ones)
5) Outlook will open and it appears to repair itself
6) You can exit Outlook and restart it normally to verify that the fix worked.
Hope it helps!