Hi everyone I'm sorry for my english I did a new install of ispconfig with Centos 7.6 as described in howtoforge perfect-server-centos-7.6 ... Then I wanted to add the SSL certificate to my main domain "hostname -f: archive.xxxxxxxx.it" and I followed the other howtoforge guide ....... securing ispconfig ...free-lets-encrypt-ssl-certificate. After creating the domain equal to the hostname -f on the ispconfig panel I activated the flag on "SSL" and "Let's Encrypt" ..... the Let's Encrypt certificates were created regularly, but seeing the website https://archive.xxxxxxxx.it I receive the usual unsafe certificate error seems to load the self-created certificate that expires 364 days ... So I checked and tested the Let's Encrypt certificates and it looks like they were created correctly in the /etc/letsencrypt/live/archive.xxxxxxxx.it/ directory and then I checked the files available for the sites and the sites enabled to see if the links are correct and everything seems ok following the symbolic links ........ So I tried to put a certificate on the admin panel as a guide: ln -s /etc/letsencrypt/live/$ (hostname -f) /fullchain.pem ispserver.crt ln -s /etc/letsencrypt/live /$ (hostname -f) /privkey.pem ispserver.key and the result ok !! https://archive.xxxxxxxx.it:8080 valid ok certificate! instead the host name of the site https://archive.xxxxxxxx.it no! always invalid! After reinstalling the entire server twice and several tests I could not understand ....., I have other servers with ubuntu and ispconfig and I never encountered the problem, it's the first time I try Centos .... Thanks everyone in advance!