The Nextcloud on the separate server is the docker AIO (all in one install). I don’t mind leaving the Nextcloud in MIAB but I want to add email capabilities to Nextcloud AIO.
I tried setting up MIAB settings in the Nextcloud mail app but the first couple of emails went to spam and after 2 or 3 other emails all further were blocked. Spamhaus says my domain is suspect so I can’t send any emails.
This is a new domain name and the IP addresses of my MIAB VPS and Nextcloud VPS do not appear to be blacklisted.
I feel that I set up MAIB incorrectly in Nextcloud.
Spamhaus has unblocked my domain after I contacted them but I am now concerned about using my MIAB because I don’t know what caused the blocking in the first place. This is a new domain and the MIAB instance is for me and my family. I have never sent bulk emails and do not need to send them in the future.
Is there a correct way to set up MIAB with Nextcloud on a separate server.
I would start with creating a specific user on the MiaB box for your external nextcloud. The follow this page to set things up.
If mails go to the spam folder, you can take a look at the headers and look for stuff like dkim and spf validation. That it is nextcloud that sends the mails should not matter.
If the receivers of the mails from your external nextcloud are all users of your miab box, delivery should be internal to the box, so there should be no issues if your ip and domain are no longer on spamhaus list.
If you still have issues, please mention the exact error messages you got and how you got them.
I followed your instructions (setting up a separate specific user for MIAB) and everything seems good so far. No spam folders, but I have only sent a couple of emails. I only need to send 20 to 30 emails per month so will only start testing it in the next few weeks.