Hi @Bryan Kelly
Welcome to our forum!
What are the steps to make the display mode “classic Outlook” the permanent and default mode.
What guide did you follow?
If you want to set it to the classic version, you just need to switch from the top right corner normally. If your Outlook client doesn't see the switch, try the following troubleshooting steps:
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.