HI Diane,
I am a retired home user of Outlook. And I mainly use it now for email, contacts, and calendar. I have a new computer now that runs on Windows 11, and it has no problem with starting Outlook Email.
But, with my last computer running Windows 10 and then 11, all of a sudden it wouldn't open Outlook when I clicked on its icon in the task bar. Accidently one day, I right clicked on the Outlook icon, and it brought up a list of options, like Calendar, Contacts, Email. I clicked on the Calendar option, and the calendar portion of Outlook started up. Then I closed the calendar, right clicked on the Outlook icon, selected the Email app, and it didn't open Outlook. So, then I went back and right clicked on the Calendar app, and Outlook started up again. From the Calendar app, I clicked on the Email icon in the upper left corner of the Outlook Calendar app, and it immediately switched to Email. Weird, right?
From that day on, whenever I needed to start Outlook Email, I went through that back door approach of opening Outlook Calendar, and then switched to Email within the Outlook app. And it worked every time. So that was my permanent work-around. And because my old laptop was so slow to open Outlook, I would usually just minimize Outlook when I wasn't using it, instead of exiting from it. Then I just needed to click on the minimized Outlook icon and it would re-open and synchronize with the email server and show new emails.
I hope that helps you get through your frustration with Outlook for now.
Terry