ADFS Authentication

I'm currently trying to figure out why this is failing.

Here is how I'm building the objects to connect the organization webservice in a go between WCF service.  The deployment is IFD/ADFS

string uname = WebConfigurationManager.AppSettings["uname"];
        string password = WebConfigurationManager.AppSettings["password"];
        //string domain = WebConfigurationManager.AppSettings["domain"];
        //Construct connection objects
        Uri _organizationUri = new Uri(WebConfigurationManager.AppSettings["url"]);
        Uri _homeRealmUri = null;
        ClientCredentials _credentials = new ClientCredentials();
        OrganizationServiceProxy _orgProxy; 
        IOrganizationService _service;

        IServiceConfiguration<IOrganizationService> config;

        //Initialize connection objects
        public void init()
        {
            _credentials.Windows.ClientCredential = new System.Net.NetworkCredential(uname, password);

            config = ServiceConfigurationFactory.CreateConfiguration<IOrganizationService>(_organizationUri);

            _orgProxy = new OrganizationServiceProxy(config, _credentials);
            //_orgProxy = new OrganizationServiceProxy(_organizationUri, _homeRealmUri, _credentials, null);
            _service = (IOrganizationService)_orgProxy;

        }

Trying to do retrieve (or any other functionality via _service)

leadEntity = _service.Retrieve("lead", leadID, new ColumnSet(true));

Then I did some googling and found someone suggested putting in the domain like this uname@domain.  That changes the error to:

SOAP security negotiation with 'https://myaddress/adfs/services/trust/13/kerberosmixed' for target 'https://myaddress/adfs/services/trust/13/kerberosmixed' failed. See inner exception for more details

The inner exception says this:

InitializeSecurityContent failed. Ensure the service principal name is correct.


Any advice on how to fix the connection would be appreciated.