Start Outlook in Safe Mode to resolve startup problems..
If Outlook does not start properly, freezes when you change settings, or you suspect that a recently installed extension may contain malware, you should start the program in Safe Mode. Then you can start troubleshooting.
Start Outlook in Safe Mode so that you can determine the cause of startup problems. Follow our step-by-step instructions or take a look at the brief instructions .
Once Outlook is in Safe Mode, you can start troubleshooting. You can find some solutions that should help you in another post on the topic of "Outlook does not start". The sections "Resetting the navigation area" and "Finding faulty add-ins" should be of particular interest to you..