How To Fix Common Email Problems [MacRx]

As an IT consultant you get accustomed to certain problems and complaints from users.  "My computer is running slow" is a universal favorite.  "You said this would only take a few minutes" is another perennial frontrunner.
But one stands out as arguably the most common end user headache: "My Email Isn't Working."
Sigh… Welcome to the club.  Email [...:]