ProtocolException with WCF Service

When I try to access WCF client, I get the following error. I was able to access my service using IE and able to reference in VS 2010. My development environment is Windows server 2008. I hosted service in Sharepoint Project server. I am stuck with this error. Please advice.

"The content type text/html; charset=UTF-8 of the response message does not match the content type of the binding (text/xml; charset=utf-8). If using a custom encoder, be sure that the IsContentTypeSupported method is implemented properly. "

Here is some data Headers from Fiddler.

GET /_vti_bin/psi/helloservice.svc HTTP/1.1 Content-Type: text/xml; charset=utf-8

MicrosoftSharePointTeamServices: 14.0.开发者_如何学Go0.4762 Server: Microsoft-IIS/7.5 X-AspNet-Version: 2.0.50727 X-SharePointHealthScore: 4

WCF HTTP Activation must be enabled on the server. If the script maps for WCF are not installed you may receive the error.