A chain certificate is a digital certificate that provides a bridge of trust between a Certificate Authority (CA) that your browser already trusts with a new and/or previously unknown CA that your browser may or may not already trust.
Prerequisites
An existing hosting account.
A hosting account with a dedicated IP address.
An installed SSL Certificate.
How to: Setup a SSL Chain Certificate
Click the Hosting Features menu item if it is not already open.
Click the SSL Certificates menu item.
Click the [Setup SSL Chain Certificate] link. If this link does not exist, you must setup a SSL Certificate first.
Paste the Chain Certificate data into the text box.
Click the Install button.