I went to sslforfree gave my csr info to them and I recieved 2 files from them: 1. ca_bundle 2. certificate.crt
I also have my original mydomain.key & the mydomain.csr I then put my .key and certificate.crt files in the exact same places you'll also find dovecot.pem, same permissions and owners, I also symlinked those files to /etc/dovecot/private , I then restarted postfix and dovecot, my mailserver works great, in testing it at https://ssl-tools.net/mailservers that The mailservers of mail.mydomain.net can be reached through an encrypted connection I'm getting this error saying "Unknown Authority" even though it shows the Authority: Certificate chain
mail.mydomain.net 89 days remaining 2048 bit sha256WithRSAEncryption Unknown Authority Let's Encrypt Authority X3
I'm running Ubuntu 18.04 postfix, dovecot, sasl, spamassassin and Webmin everything updated to latest daily. I've been trying to figure this one out for about 2 weeks 12 hours per day, I could really use some help !