Symptom

• Unable to install wildcard certificate for a domain or sub-domain in Domains > example.com > SSL/TLS Certificates, details show:

  Invalid response from https://acme-v02.api.letsencrypt.org/acme/authz/RHm6H_sWJY3zeKbRluriIimo-FQ2RlGasXXXEEfyVZmo.
  Details:
  Type: urn:ietf:params:acme:error:unauthorized
  Status: 403
  Detail: No TXT record found at _acme-challenge.example.com

• Domain DNS Zone is hosted and managed by external DNS hosting provider.

• Plesk DNS management is enabled in Domain > example.com > DNS Settings.

Cause

The _acme-challenge.example.com TXT DNS record needed by Let's Encrypt is invalid or absent on the external DNS provider side.

Resolution

• Issue a new Let's Encrypt Wildcard Certificate by adding the _acme-challenge.example.com TXT DNS record on the DNS hosting provider side as is instructed on this article.