In this article we describe how you can create a free Lets Encrypt certificate.  You should secure all your domains with an SSL certificate so that the data is always encrypted when transferred over the Internet. <br />
Log in to the Plesk web interface. Find the domain you want to secure and click on &#8222;SSL/TLS Certificates&#8222;. Click on &#8222;Use for free&#8220; to protect the domain with Lets Encrypt. In the dialog that opens, enter your email address and click &#8222;Use for free&#8222;.  The setup may take a few moments. If everything worked, you will get the message &#8222;The SSL/TLS certificate has been installed on Meine-Webseite. de&#8222;. <br />
Lets Encrypt administration in Plesk<br />
Alternatively, you can request a wildcard Let&#8217;s Encrypt certificate that is valid for all subdomains.  This way you only have to use one certificate if you use multiple subdomains for one domain.