Currently we are running several domains on our VPS. At this moment we want to certify our mail server (mail.dutchinnovisiongroup.com) with Let’s Encrypt. We already have succesfully installed a SSL Domain Certificate for our domain (dutchinnovisiongroup.com and a SSL Server Certificate for Plesk Server.
To secure our mail server, we should click the [Change] link next to “Certificate for securing mail” and select the “Lets Encrypt certificate (server pool)” from the drop-down list, and click OK. But for some reason this option seems not available. And in the list of Server Certificates only the default certificate is visible. What do I oversee?
And if I want to SSL secure the mail servers of all the different domains we are running on our VPS, do I need to use the SSL Certificate of that particular domain or can I use the Server SSL Certificate?
Any help is and all suggestions are more than welcome.