Core Service error: The HTTP request is unauthorized with client authentication scheme 'Negotiate'

Question

I am using SDL Tridion 9.6 trying to create a custom application. While trying to connect to wcf core service, I am getting the following

Error:

The HTTP request is unauthorized with client authentication scheme 'Negotiate'. The authentication header received from the server was 'Basic realm="domain"'.

Any help is appreciated.

class Program
    {
        static ICoreService GetNewClient(string username, string password)
        {
            var binding = new BasicHttpsBinding()
            {
                MaxBufferSize = 4194304, // 4MB
                MaxBufferPoolSize = 4194304,
                MaxReceivedMessageSize = 4194304,
                ReaderQuotas = new System.Xml.XmlDictionaryReaderQuotas()
                {
                    MaxStringContentLength = 4194304, // 4MB
                    MaxArrayLength = 4194304,
                },
                Security = new BasicHttpsSecurity()
                {
                    Mode = BasicHttpsSecurityMode.Transport,
                    Transport = new HttpTransportSecurity()
                    {
                        ClientCredentialType = HttpClientCredentialType.Windows,                        

                    },
                    
                    
                }
                
      
            };
            //hostname = string.Format("{0}{1}{2}", hostname.StartsWith("http") ? "" : "http://", hostname, hostname.EndsWith("/") ? "" : "/");
            var endpoint = new EndpointAddress("https://xxx.xxx.xxx.xxx/webservices/CoreService201701.svc/basicHttp");
            ChannelFactory<ICoreService> factory = new ChannelFactory<ICoreService>(binding, endpoint);
            factory.Credentials.Windows.ClientCredential = new System.Net.NetworkCredential(username, password);
            return factory.CreateChannel();
        }
        static async Task Main(string[] args)
        {
            var client = GetNewClient(@"domain\userid", "password");
            var user = await client.GetCurrentUserAsync();
        }
    }

Answer 1

In your client code, you're configuring Windows Authentication ( ClientCredentialType = HttpClientCredentialType.Windows), but the error returned by the CM server says that it expects HTTP Basic Authentication.

Most likely, your CM server is configured for LDAP Authentication (which uses HTTP Basic Authentication between client and server). You can verify this by checking if the LdapAuthenticationHttpModule is enabled in the Webservices web app.