How to Retrieve Deleted Mailbox in On My Mac

Hi there, TT2752,

If I understand your post, you accidentally moved a mailbox from On My Mac in the Mail app that contained important emails, and are not able to find it. I'm happy to help!

In order to delete a mailbox in Mail, you must purposefully do so by right- (or Control)-clicking on the mailbox folder and choosing Delete Mailbox from the menu that pops up: Create or delete mailboxes in Mail on Mac - Apple Support. If you didn't do that, it sounds to me like the mailbox folder got tucked away in another folder in the Mail app.

If the mailbox folder was moved into another folder, there would be no confirmation for the move. Mailbox folders that contain other folders appear with an arrow to the left of the mailbox name, though. So, my recommendation would be to scroll through the mailbox folders in the sidebar, expanding any that have this arrow. You should be able to find the missing folder, and drag it back out to your sidebar.

If you still cannot locate the folder, you can also use the Search bar in the upper right of the Mail app to search for the mailbox folder name. A drop down will appear giving you options to search for different criteria, including the mailbox itself.

Thanks for visiting the Apple Support Communities.

Best.

You are very welcome, TT2752!

It was our pleasure to help.

Cheers!