My large application user base means we're constantly having a steady stream of users with hard and soft bounce issues as we send them broadcast emails.
We're building some internal tools to make it easy for staff to follow up the hard bounces via alternative channels, however maximising self-service is preferred.
What's the best way to tell a (non-technical) user via an application interface 'hey, we noticed your email address hasn't been working since $date because it's been throwing the error $error' in a useful enough way that won't cause the user to freak out and take meaningful action?
Often ESPs will be provide transient false hard-bounces also, causing our system to back off and internally black list the email service for say 7 days. Is it worth providing a UI to the user for them to remove their address from the internal blacklist and resume email sending? Or am I looking at this wrong?
Yours, a humble web sysadmin and email guy.
 - perhaps I should force the user to re-validate their email address in order to get themselves off our block list early?