If you send email campaigns long enough, you will run into spam filter issues.  As a legitimate email marketer you can still expect 20%+ of your emails to just get lost in cyberspace, mostly due to overzealous spam filters.  SPAM filters / firewalls use multiple techniques to determine whether your legitimate business email is SPAM .   Today’s filters rely heavily on your domain and server reputation, but most filters still factor in your email’s content, and are based on the spamassassin engine.  Content-based filters review your content and assign points each time they see something that looks like a spammy phrase, and certain criteria get more points than others.  If your campaign’s total “spam score” exceeds a certain threshold, your [...]