WCF : Could not establish trust relationship for the SSL/TLS secure channel with authority error

Question

I have a client site that when a button is clicked it calls a wcf web service. The client site is http, while the url for the web service is https and requires a certificate

Answer 1

Found the problem.

The root certificate which the host of the web service uses was not trusted by my server. (not sure why it was on my local machine and not my server). I found this out by opening the host's url in a web browser from the server to view their wsdl and got the security warning.

Remedy: went to the issuer's site downloaded their root cert and added to my trusted root certifcation authorities.

Bam, it works now.