422 Unprocessable Entity at sending emails with bitnami and plesk

[pfaffman (Jay Pfaffman)]

Welcome aboard, Captain!

@Captain464

using the bitnami docker image

We don’t know much of anything about how Discourse works on Bitnami.

Troubleshooting Bitnami Installations

@Captain464

if I use another mailing service like Office365 or GMX, it’s working. But if I use different accounts on this plesk server or another domain on the same server, I always get the error above.

Then there is something wrong with that mail server or your configuration. The recommendation here is mostly to use services like the ones that you have working, because they work. There are a bunch of topics about that error, so you might check them. One reported that they were using the wrong port.