Unable to secure webmail in Plesk for a no-hosting domain with aliases: Get it free button is greyed out

Symptoms

• The 'Get it free' button is greyed out while trying to secure the domain with a Let's Encrypt SSL certificate.
• One or more alias domains are associated with the domain.
• The domain is set as No hosting.

Cause

Domains of type "No Hosting" cannot be secured with SSL when aliases are present due to a known bug in the SSLIt! extension identified as #EXTSSLIT-2073.

Resolution

There is currently no permanent resolution. Until the bug is resolved, the aliases must be removed before SSL installation is possible. Once the certificate has been issued, the aliases can be re-added or reconfigured as Forwarding domains.

Refer to the following articles for detailed steps on removing aliases, adding Forwarding domains and issuing SSL certificates:

• How to remove a domain / subdomain / domain alias from Plesk
• How to create a domain forwarder in Plesk?
• How to install Let's Encrypt SSL certificate for domain in Plesk?