I am running my own email-server for some time now. It started out of curiosity and went live after my hosting-provider got hacked several times and I then was sick of it. It’s not as hard as people make one believe when it’s just for a few email-addresses. Still I check the server every now and then.

The setup and what I do in between might be a separate blogpost (or actually several) but today I just want to write about one thing that nagged me really deeply and where the solution was pretty easy. I had to think about it when Rob Allen today wrote about DKIM, SPF and DMARK.

What happened

Whenever I wanted to send an email to an outlook.com (or outlook.de or hotmail.com) address, that email just didn’t get through. It was considered spam and I received a nice feedback in the mailserver-log: