Important: Installation is a two-step process - ensure you follow both steps listed below.
If successful a message is returned 'Certificate Successfully Installed'.
If there are any errors the old certificate will replace the new certificate that you have just sent to the server and you will be required to enter it again.
Now click Up Level to return to the Domain Administration page.
To ensure your certificate is trusted by all browsers you need to install a rootchain certificate for the domain.
Using your SSL Certificate to secure logging into your Plesk Administrator
If you are applying your certificate to the Plesk control panel (in order to secure your login) you will need to login to Plesk Administrator and select Server.
Select Certificate and complete the above instructions as per applying your SSL certificate to a domain.