@scooke thanks, I know it can be frustrating to help someone who is trying too many things at the same time and who doesn't want to read the abundant docs everywhere. Email does feel like a black box. Right now there are MX records from titan.email (which I bought from name.com when I got the domain). I can remove those. But then how do I check test emails? I take what you mean is that I should use one of the cloudron webmail apps?
This is what I have on my DNS (name.com) for that domain:
However, what is receiving your email? If you are using Cloudron to manage your email, it doesn't make sense to use an external SMTP
Who is receiving email: gmail accounts for testing (2 gmail, one gsuite) and one titan.email for good measure.
Problem is that when I used cloudron with no relay, email did not arrive to anything but spam. As recommended here, I tried to mark as 'not spam' and reply to these emails, but that didn't solve the problem. It might be I need to do this more and be patient, but this doesn't help: I wanted to have launched this community weeks ago; by going self-hosted I'm adding a few days to the launch. Which is fine, this is a skill I want to learn about self-hosting and even encourage more people to do it.
What I don't want to learn how email works and all the certification layers that need to happen for email to 'just work.' This seems to be a rabbit hole, and an exercise in Yak shaving. If I have to, I will, but I have dozens of things that are higher priority now. Email is smack in the middle of everything. Unless you solve it, you cannot do self-hosting. And it is unpleasant: anyone who doesn't want to have anything to do with sysadmin/servers (99% of the population) will not go through this hoop. I've been on desktop linux for > 20 years and I find it too convoluted. You need to understand way too many things to get it to work. It's like going to a shop to buy a piece of paper, which is just a prerequisite for what you wanted to do, and getting a lecture about growing trees and making paper. A lecture that if you don't attend, you will get no paper. Period.
I'll push it through and get it done. But my hopes of getting anyone around me to get this done themselves have dropped to zero.
This could be a problem: 'test mode, we are reviewing your account'
EDIT: this might explain everything:
Might be waiting 24 hrs 'solves email'. I would still love to know if I should remove the MX entries for titan mail and use one app from cloudron to read email from this domain. The mixed mx entries might be causing trouble.
I think I have set up SPF, DKIM, DMARC with postmark as they instructed. My reason to move to postmark was to avoid getting stuck in spam folder for the time it takes for the domain to warm up. Which coulld be days, and that would kill the project.