Comment on How To: 100% Trouble Free Email for WordPress with Mailgun by Bo Lais.
For anyone unaware there have been significant Mandrill Policy Changes as of yesterday (Feb. 24, 2016) that require a paid Mailchimp account in order to use Mandrill any longer. There is chaos stirring on the internet regarding this very bold decision by Mandrill yesterday. Additionally, they gave everyone a very short notice to get moved to another provider before your account will be terminated for non-compliance.
