Add the ComodoClass3SecurityServicesCA.crt certificate as
Trusted Roots:
Then attach each certificate in turn to your website's Key
Pair in the following order. At this point your Key Pair will be
black.: Yourdomain.crt ComodoClass3SecurityServicesCA.crt GTECyberTrustRootCA.crt
Your Key Pair will turn now be green.
Once completed, you MUST delete the
ComodoClass3SecurityServicesCA.crt
Ensure GTECyberTrustRootCA.crt remains in the Trusted Root area.
Stop and Start the server, your site can now be found
using the https entry