It really got worse. In the past years (always the same IP, good reputation, DKIM), I had a few mails land in the spam folder of gmail users, but it did not hap

It really got worse. In the past years (always the same IP, good reputation, DKIM), I had a few mails land in the spam folder of gmail users, but it did not happen very often. This week I encountered the following situation the first time: 1. I received an email from a Google apps (or whatever it is called) user. My response to that email landed in the spam folder. 2. I exchanged one or two mails more with another person in the same organisation without problems. 3. Suddenly my response got rejected. I tried sending via various means such as via Thunderbird, via mobile on 4G, via mobile on Wi-Fi, changing the content slightly... No chance. My email got rejected. In the I ended up calling the person from number 1 on his mobile to get the second person's mobile number... Needless to say, I have been less than pleased. Person 1 was very surprised about their spam filter misbehaving, but at least I can now offer an excuse by pointing to this blog post...