Shared mailbox cannot be pinned to Favorite

I was able to add my Shared with Me Inbox folder to the favorites, but I am part of the Targeted Release and located in the USA. 

Admin Message Center: Microsoft Outlook is updating to allow users to add shared folders to Favorites, starting in early February 2025 for Targeted Release and March for General Availability.

If you find this information helpful, please mark it as the best response which will assist others.

3/24/2025 #traccreations4e

I just now just was able to add my shared mailbox to favorites in New Outlook. Give it a try, might work for you too. 

This is a known issue with New Outlook. Apparently a fix is rolling out now - not sure when it will actually appear. See here: https://www.microsoft.com/en-US/microsoft-365/roadmap?filters=%5B%22Desktop%22%5D&searchterms=388913

I just tried to do it in the new Outlook but it didn't work, even didn't success manually adding the shared mailbox, better to return to the classic outlook until they address this issue. 

If you are unable to add a shared mailbox to your Outlook Favorites, you can try the following:
1. Check permission: Make sure you have “Full Access” permission.
2. Right-click: Right-click on the shared mailbox in the folder pane to see if there is a “Show in Favorites” option; if there is no such option, it may be a permission or setting issue.
3. Update Outlook and clear cache: Make sure you are using a version of Outlook that supports this feature and check if it is the latest version.
Clear cache: Close Outlook and delete the contents of the %localappdata%\Microsoft\Outlook\RoamCache folder (only affects the local cache).
4. Re-add shared mailboxes: Try removing and re-adding shared mailboxes.
5. Use Outlook Web (OWA): If you are having problems with the desktop client, try operating through the web version of Outlook.