Gmail and Hotmail marked as spam

Question

First of all, I want to thank you for your time. I\'m having a hard time getting my head around this problem.

With reference to this thread we\'ve dediced to implem

Answer 1

First, I would suggest using Swiftmailer over PHPMailer. But regardless, your issue isn't what software you are using to send your email. You should head over to http://mxtoolbox.com/ and see what it says about your email domain. You should have the correct reverse DNS setup, in addition to making sure you have a SPF record setup in your DNS.

It seems your reverse DNS is not setup correctly, at least not for koopte.be.