Thanks for the tip. I tried it and it didn't work. I have now activated the LE certificates from the proxy manager again and can send emails despite the certificate message in Outlook. I have already invested hours and will soon swap the Fritzbox for a Mikrotik, maybe it will work better then. I won't be investing any more time here in the next few days. Thanks for the support.
Hello! I tried a lot of things and also adjusted them in Dovecot. I did another SSL check online. This is the result: Certificate #1 of 1 (sent by MX): Cert VALIDATION ERROR(S): self signed certificate So email is encrypted but the recipient domain is not verified Cert Hostname DOES NOT VERIFY (vps2.domain1.at != vps2.domain2.at) So email is encrypted but the host is not verified does anyone have a tip? There is a certificate on the mail server, but the domain with which I installed ISPConfig locally is still there (no ports 80 and 443 were open). Thanks!
I have been following this thread and all I can say is ISPConfig server must have ports 80 and 443 opened for it to get LE certs for any domain inside it including the server's domain itself since it only uses http challenge to get them. Do not ignore the fact that with one public IP, dynamic or fixed, one may not be able to share those ports between ISPConfig server and proxy server, and may only use one them to obtain LE certs and not both. One of the solution will be to use dns challenge for the internal ISPConfig server to obtain LE certs, but this is not yet formally supported, as such only manual unsupported method is possible. The other possible method will be to copy or share the LE certs folder between the two servers but I read that've already been attempted via some script though I am not sure what is the result so far.