I used Apple Mail for many years, starting in Mountain Lion! As each new version of OS/X came along, everything got updated. Gave me some problems for the series of versions from Mavericks to High Sierra, as each release brought in its own selection of bug-regressions, and wasted many hours after each OS upgrade simply repairing the damage to my message-base inflicted by the upgrade.
I also found I had some serious but mysterious bugs in mail that others did not experience, as well as the well-know ones! In the end I decided I’d had enough, and switched to a succession of other mail clients, none of which have proved adequate for my needs. I now want to go back to Apple Mail!
Because some of the bugs I used to experience seemed to be unique to me, I suspect that my Apple Mail installation has, over the years and over many OS upgrades become corrupt, and so before I start trying to use the app again, I really want to get a clean install. With an app-store app this would be easy - do a full uninstall of the app using CleanMyMac, make sure that all data has gone, and then re-download the app from the App Store. Unfortunately, Mail is considered to be part of MacOS, and cannot be uninstalled, nor installed except as part of an OS installation.
Does anyone know if there is any way to get a fresh Mail installation except as part of a nuke and pave exercise?
Alternatively, is there any way of selectively excluding apps from the migration process after installing a new MacOS version? (I need to upgrade to Mojave, so that might be an opportunity!)
You can probably set up a new user account on your Mac, add your mail credentials, and let it pull everything down from the server(s) anew. But it sounds like you’re ready for a nuke and pave before Mojave anyway.
Just removing the email account from System Preferences>Internet Accounts will result in the local mail database being removed. Adding the account will prompt a complete re-download of the database.
It isn’t possible to remove and reinstall an individual system application like Mail, you’d have to do a complete OS reinstallation.
I have to say I’d prefer NOT to nuke & pave, because (unless they’ve made the obvious changes to Migration Assistant) if I don’t want to migrate Mail then I can’t migrate anything else - meaning it all has to be reinstalled and reconfigured manually, which is a total pain.
Have you tried removing that email account from Internet Accounts and re-adding it to see if that solves your problem? Until you do that we don’t need to start thinking about a nuke and pave.
If you do find yourself needing to nuke and pave, you can avoid migrating the email. if you are migrating from a clone or Time Machine backup, remove the email account from your machine BEFORE you do your final clone/TM backup. Then when you nuke and migrate, that mail account will not be part of the backup/clone, and thus won’t be migrated. That way you can nuke, pave, migrate, and then manually set up that email account on the newly paved machine.