[wcf] Content Type text/xml; charset=utf-8 was not supported by service

First Google hit says:

this is usually a mismatch in the client/server bindings, where the message version in the service uses SOAP 1.2 (which expects application/soap+xml) and the version in the client uses SOAP 1.1 (which sends text/xml). WSHttpBinding uses SOAP 1.2, BasicHttpBinding uses SOAP 1.1.

It usually seems to be a wsHttpBinding on one side and a basicHttpBinding on the other.