Using older versions of Outlook for Mac for personal email and calendar
Dear Paul Beatrice
Good day! Thank you for posting to Microsoft Community. We are happy to help you!
Based on your description, I have a general understanding of your problem, please first kindly try to transfer to New outlook for Mac and then check the result if you are using classic outlook for Mac. If you still need help, please kindly try to create a new profile, and add your account to the new profile and check if the same error still occurs, in this process to prevent you from losing important data, please also kindly try to back up your data in advance, thank you.
If your problem persists, since we specialize in technical support for Microsoft 365 Business Exchange Online, which is not professional for the Outlook for Mac, in order to better help you and no longer waste your more time. I recommend that you ask for help from our dedicated team, where technical engineers specialize in these related issues, and experts will focus on inquiries to further assist you, for details, please kindly refer to: Contact support within Outlook for Mac
Thanks in advance for your understanding! Your patience and cooperation will be highly appreciated. Hope you all the best!
Sincerely,
Kerry Chen | Microsoft Community Moderator