I permanently solved it using these instructions, in particular the ones under repair access control. In summary this is what you need to do:
- Open your keychain on client.
- Select login and Passwords respectively on the left panel boxes.
- For each and every email account, get info (command I) and under Access Control, add the Mail.app.
- I noticed I had more than one entry for each of my mail accounts, one having mail.app, and the other not. All of them need to have Mail.app added, if not already present.
- Launch Mail, and if it does not readily connect, hit the ‘~’ sign next to the one of the inbox’es. Enter password(s) for one last time, then it sticks.
Yes this is a bug. Unfortunately, my respect for Apple has taken a serious hit in the last two years. It no longer ‘just works’.
Mail Keeps Asking For Password
Mail Keeps Asking For Password – Take 2
Mail Keeps Asking For Password – Take 3
Mail Keeps Asking For Password – Take 4
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