I am trying to setup my eNewsletter plugin with my one.com

I am trying to setup my eNewsletter plugin with my one.com email address. But no matter what i try (except the thing i obviously haven't tried yet) will work! What to do?
I have these setings:
send from: news@mamuti.dk
smtp server: send.one.com
Username: news@mamuti.dk
pass: ********
Port: 465
SLL on