Email security settings

Well, it looks like I fell victim to this (or some variant) today.  Outlook 2016 was working fine up until 1:25 PM (local time zone) -- that's the date/time stamp on the last email that successfully sent.  Since then, nothing will leave my Outbox.  Incoming is working fine.  Just can't get anything out.  And it is now 10:22 PM (local time zone).  Both Cox online chat and later a call to Cox tech. support confirmed there is a known system glitch affecting some users that they are working on.  Um, for 9 hours?  Really?  You can't fix (or figure out) what amounts to a denial of service for 9 hours?  Let's see now, I'm paying for a service.  That service is not being provided.  It seems like I (and everybody else not getting the service they paid for) should get some money back?  Makes sense to me.

Neither I or my wife received the warning notification -- presumably because our settings were actually correct.  But even so, it is not January 25th yet, so whatever was working before SHOULD STILL BE WORKING.  But -- poof! -- it is not.  Both my wife and I use Outlook 2016 (on different computers), and neither of us can send mail.  For whatever value it might serve, here are screenshots of my settings and the accompanying failure message on "Test Email Settings":

Please provide a solution that works.