Third party licensed email delivery software will make sure that relevant email notifications will get to your customers mail box and not get caught in spam filters. (datingfactory.cz)
These systems can pose an even greater threat to preservation efforts by increasing the risk that relevant emails get deleted as part of the regular retention cycle. (exterro.com)
Basically for a free promo, do list - trades with authors in your genre, or book promotions on the book promo sites with relevant email lists. (creativindie.com)