This option would automatically install a certificate on all domains. Since this is a global setting for all customers, it cannot be enabled individually.
- Renew your certificate as described in chapter 2.
- Select the option Include a "www" subdomain for the domain and each selected alias, so that www is also secured.
Let's Encrypt uses rate limits (external link). These limits only allow a certain number of new certificates to be created for a domain within a certain period of time. Since the domain netcup.net is for all standard domains for all web hosting customers, it is a matter of luck that a certificate can be issued. We therefore recommend using your own domains.
These limits are set by Let's Encrypt and we have no influence over them. In urgent cases, we recommend an alternative certificate authority or one of our paid SSL certificates.

