[Editor's Note: If your e-mail program is ailing, find out what's not causing the problem.] Ed Henrich - ClickZ - 3/4/10 Your e-mail program is like a person: sometimes it's robust and healthy, and at other times, it's sick. Last year, my wife woke up with the right side of her face paralyzed. The ER quickly ruled out a stroke and then ruled out a brain tumor through a sequence of tests. Thus determining the cause was neither a stroke or brain tumor, but Bell's Palsy.

Just like my wife's situation, the best tests are those that allow you to rule out the most serious problems. So, to diagnose what's ailing your e-mail program, begin by using a methodical approach to find out what's not causing the problem.

Identify the initial symptoms (spam complaints, falling conversion, falling order value) and develop an initial set of hypotheses. Then apply a series of tests to rule out those that aren't contributing causes. Read the full story.