Install SSL – install Intermediate Certificates
Open the WHManager – click Activate SSL Certificate in the SSL/TLS menu.
You will see a screen with three boxes on it. Your issued certificate, RSA private key and certificate bundle must be pasted into boxes 1, 2, and 3, respectively.
In the first box, paste in the contents of your issued SSL certificate. If the certificate file is on your server, you may use the Fetch button to copy it from the file.
In the second box, paste in private key which was generated when you created the CSR.
In the third box, paste in the certificate bundle (sf_bundle.crt).
At the top of the page click Do it.