Hi, Alex. Thank you for coming to the forum. My name is Femi. It is worth noting that this is a user community, and we are all users here, much like yourself. While we strive to assist and share insights, we are not Microsoft directly.
To resolve your issue, I pulled the following steps from (https://learn.microsoft.com/en-us/answers/questions/952402/my-favorites-have-disappeared-in-outlook) where Joyce Shen suggests;
"1 Check if you disabled the Favorites section.
2 Check if you switched to the Folder List Navigation.
In Mail, click View > Folder Pane > Favorites.
If you turn off Favorites, and then turn it back on, the same folders appear.
Tip: If the Favorites command is missing, you are probably in a special view known as the Folder List, not Mail. On the navigation bar, click Mail.
To switch between the Mail Navigation and the Folder List Navigation, you can use the Navigation Panel at the bottom left or use their keyboard shortcuts.
CTRL+1 Mail Navigation CTRL+6 Folder List Navigation"
I hope this helps, let me know if this contradicts what you need. I remain helpful in answering any more of your questions.
Best Regards,
Femi.
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