Before sending out your Email marketing Campaign, make sure use spam assassin to rank your Email on a score to determine how likely it is that it will be regarded as spam. The higher the number is, the more likely it is that your Email will be marked as spam. One thing we have become aware of is people putting unnecessary punctuation marks in their Emails. Try not to put any hyphens in your Email header, and never place them in the middle of a word. This is a sure-fire way to get your Email marked as spam.