Q: Citrix Receiver - RapidSSL SHA256 CA - G3

So i have installed the Citrix Receiver on my MacBook to test out corporate Citrix environment for some Mac users out in the field.

Now, everything is working just fine for Microsoft Users however, when ever a Mac user tries to launch an application they are getting the following error;

"You have not chosen to trust "RapidSSL SHA256 CA - G3", the issuer of the server's security certificate"

However, I have added the whole certificate chain to the Keychain Access under both Login and System. These comprise of the Corporate Wildcard Cer, GeoTrust CA .cer and RapidSSL CA.cer.

Is there something I am missing or are Mac users not going to be able to carry out their work on Apple Products but only on Microsoft Products.

This never was an issue before, only on the new OS