If outlook will not start there are many things that can cause this. This link will step you through the many steps.

https://www.howto-outlook.com/faq/outlookdoesntstart.htm

Outlook also has many switches that can be used at start up. https://support.office.com/en-us/article/command-line-switches-for-microsoft-office-products-079164cd-4ef5-4178-b235-441737deb3a6#ID0EAABAAA=Outlook