A bit more info: this post http://www.tldr.love/20171029/migraron-http-https-link-assitant-com/ is not allowed. As soon as I have removed this post the mailing has gone without problem. Any clue why it cannot be added to the mailing list? thank you!
I have tried to send a short mail to a test list and the mail arrives without problem. Is there a maximum size maybe?
