Apple Mail and AOL
Apple Mail on my Mac has problems synching my AOL mail. The AOL account is supposedly active, and all the mailboxes appear, but Mail shows the exclamation point (!) and can not synchronize with the AOL server or get new mail. Up to now, the problem has been intermittent; I've fixed it by quitting Mail, restarting it, and telling it take AOL online and synchronize mail. Today that doesn't work, and neither did a system restart. Any ideas? I'm running OS X 10.14.3 on a year-old MacBook Pro w/ touchbar.
MacBook Pro 13", macOS 10.14