Open Mail
Click Mailbox - New Mail OR right-click on existing Mail Inbox and Add new Mailbox
New Mailbox appears AND then disappears.
Have cleared cache have removed old folders
Nothing works Mail cannot 'retain' a new folder. the new folder appears and then disappears from view
Start with this...
Safe Boot, (holding Shift key down at startup), does the problem occur in Safe Mode? Could take 10 minutes.
Safe mode attempts to repair Disks & clears lots of caches & loads safe Drivers, & prevents loading of 3rd party extensions, so if Safe Mode works try again in regular boot.
I think I realised the problem - not our Macs. The mail account - I logged-in direct and tried to create a new folder and it failed but with message reached limit of folders. Free account.
Had to do some pruning of folders but I know the problem now.
Appreciate your advice - good to know
Good work on your part, thanks for reporting back! :)
Mail New Mailboxes Disappear
