Unable to issue a Let’s Encrypt certificate for a domain in Plesk when SSL/TLS support is disabled

Symptoms

• The following warning is displayed in Plesk at Domains > example.com > SSL/TLS Certificates:

  Warning: SSL/TLS support is disabled for example.com.
  To resolve the issue, please enable to SSL/TLS support ("Websites & Domains" > "Hosting Settings") for this domain and try again.

• The "Get it free" button is greyed out or it is only possible to secure webmail for a domain (other options are missing) at Domains > example.com > SSL/TLS Certificates > Install:

  

Cause

It is not possible to install an SSL certificate when SSL/TLS support is disabled. The behavior, when there is no warning about disabled SSL support, is considered as a bug with ID #EXTLETSENC-871.

Resolution