Here is how to alphabetize Mac mail folders automatically again:
- Close the macOS Mail app, if it is currently open.
- Launch Finder app. While pressing the option key on your keyboard, click onto the ‘Go‘ menu and then select ‘Library‘.
- Scroll down till you find the ‘Mail‘ folder and open the folder.
- Within the Mail folder, you will find one or more subfolders named like V1 / V2 / V3 …., in my case it is named ‘V6’.
- Trash all ‘Vx’-folders. Note: Do not finally delete them until you are sure you will not need them anymore.
- Launch macOS Mail app. All email accounts will be synced again. This can take a while. After the sync is complete, all of your mailbox folders are shown again in alphabetical order.
Note:
- Mainly iCloud mail accounts are affected by mailbox folders not sorting in alphabetically order. However, this fix works for Gmail, Outlook and any other email accounts, too.
- If you’re using IMAP or Exchange and have all your messages stored on a remote server, you shouldn’t be able to delete those messages through this process. If you have locally stored mailboxes, make sure they’re archived via Time Machine or other backup software!
- The fix was tested succesfully on macOS 10.14 Mojave.
Fix macOS mailbox folders (iCloud, Gmail, Outlook.com,…) not be sorted alphabetically by deleting the Mail library and automatically resyncing all mailbox accounts.
Stay tuned ! 😉