Symptoms
-
Unable to renew Lets Encrypt certificate in Home > Domains > example.com > SSL/TLS Certificates > Reissue Certificate with the next error:
Error: Let's Encrypt SSL/TLS certificate installation failed:
Remove certificate failure: One of the certificates you are going to delete is used for securing Plesk. -
Plesk (and mail server) secured in Home > Tools & Settings > SSL/TLS Certificates with the certificate issued for
example.com(e.g. the certificate name is Lets Encrypt example.com) -
The server hostname differs from
example.com
Cause
Plesk (and mail server) is secured by the same certificate as the domain example.com. This certificate cannot be deleted.
Resolution
As the best practice in general, it is better to use separate certificates to secure Plesk with the mail server and domain.
Secure Plesk (and mail server) with a unique certificate:
To secure Plesk and mail service:
- Log into Plesk
- Go to Home > Tools & Settings > SSL/TLS Certificates > Let's Encrypt
- Set the server hostname as the Domain name
- Press the Renew button
- Go to Home > Tools & Settings > SSL/TLS Certificate
- Change the Certificate for securing mail to Lets Encrypt certificate (server pool)
To secure domain:
- Log into Plesk
- Go to Home > Domains > example.com > SSL/TLS Certificates
- Click the Reissue Certificate button