Resolved Mail-Problems in Plesk Onyx

[Talion]

Hello,

I am running a dedicated server with Plesk Onyx, but have serious problems with the configuration of email.

1.) Not able to open Webmail -> Website not available. Server-IP of webmail.website.de was not found.

Webmail-Services are activated. Neither Horde nor Roundcube work. The Plesk Manual is not really helpful in this.

2.) Mails are not going out. They are always going to the queue in waiting position as deferred message.

If you need more information, tell me what you need. If someone has a step by step guide to check possible errors, I would be glad.

 

[Ales]

There could be several reasons for the issues you're experiencing. DNS, firewall, blocked ports, etc. We'd need to know the actual hostname of your server and webmail address to help finding out what is going on.

 

[Talion]

The hostname is cosmozine.de, the webmail address is webmail.cosmozine.de

 

[Ales]

Your domain uses the following name servers:

ns1047.ui-dns.org
ns1067.ui-dns.de
ns1076.ui-dns.com
ns1091.ui-dns.biz

I queried for the DNS record webmail.cosmozine.de and it doesn't exist in the above DNS.

My guess is that you're using external DNS and the changes you are making in Plesk aren't reflected there. In other words, while webmail might indeed be enabled in Plesk, the needed DNS record wasn't created in the external DNS.

This can be solved in two ways, first, host and use your own DNS, or, second, make sure that the external DNS is synchronized with whatever records need to be added or changed for your domain.

As for the outgoing mail, first I checked the connectivity on your server's port 25 and the mail server responds. So, that's ok. I noticed that it uses a self signed certificate, but that should not prevent mail from going out. What does prevent normal operation is a missing reverse DNS record for the IP of your mail server.

The rDNS can't be set up in your DNS, it is something your dedicated server provider must do for you. Some providers have control panels where their customers can configure the rDNS themselves, some don't and customers need to contact their user support.

Also note that the MX records for your domain point to mx00.ionos.de and mx01.ionos.de, which are located on different servers, not on yours. Unless you change this, even once your outgoing mail starts working, your incoming mail will still be directed elsewhere.

BTW, I noticed that the Let's Encrypt certificate used for your Plesk control panel access expired few days ago. The certificate is for the cosmozine.de but it is actually a different certificate than used for the domain itself. The latter is still valid.

That's about it. There might be ore issues, but if you start with these, you'll be much closer to your goal.

Looking at the above I can't help thinking that all this might seem complicated. There are quite a few details that need setting up... Still, once you get things running correctly, it will all come into place and begin to seem natural.

 

[Talion]

Thanks so far. You were a big help. I changed some settings now and it seems to work.