Hi @Brooke Levy,
Thank you for posting your question in the Microsoft Q&A forum.
I would like to provide you with the following information:
For Legacy Outlook for Mac, to display the Folder Pane again, please follow these steps:
On the menu bar, select View > Sidebar.
If the Folder Pane still does not appear after performing the steps above, please try switching to New Outlook and then switching back to check whether the issue still occurs.
Select Help > Revert to New Outlook.
I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.
Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.
I look forward to continuing the conversation.
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