Promo emails being marked as spam is an issue that in most circumstances can be avoided with a basic understanding of how spam filters work.
How Spam Filters Work
Many ISPs have special routers for their email domains that analyze all incoming emails. The router can automatically block emails that come from certain addresses (those on the "blacklist" of known spammers), and they will also filter out emails that contain certain trigger words in the subject.
Email filters examine the words in the email subject and body looking for words or phrases commonly related to spam. Your email is then given a score and the higher the score the better chance of it being marked as spam. This "spam score" depends very much on how strict that particular spam filter is configured. This varies from ISP to ISP.
Even if your email gets past the router on your DJ Recipients ISP, it may also have to get past the filter on their email inbox. Recipients can now tell their mailboxes to automatically delete messages that have trigger words in the subject, or that come from "wrong addresses".
Things You Can Do to Help Your Campaigns
It is recommended that you get your DJ Recipients to add firstname.lastname@example.org to their contact list/address book. This works especially well for Gmail and Hotmail accounts. Also, it is advised that you send out your promos in small batched to avoid 1 ISP getting hundreds of the same mail to arrive in a short space of time.
Things To Avoid With Your Campaigns
Using quotation marks, dollar signs and exclamation points in subjects will frequently trigger mail filters, as well as using all capital letters (shouting).
Avoid using sexual phrases, medicine names, watch brand names and the like. Any common words and phrases that you use in your subject and description text that are often associated with spam will give your email a higher spam score.
Below is a sample list of words/phrases to avoid
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