The HTTP request is unauthorized with client authentication scheme 'Ntlm

Question

Hello I have a wcf service i need to call but it still respond me with error:

System.ServiceModel.Security.MessageSecurityException: 'The HTTP request is unauthorized with client authentication scheme 'Ntlm'. The authentication header received from the server was 'NTLM, Negotiate'.'

My code looks like below:

Client creation:

var binding = CreateBinding();
var endpoint = new EndpointAddress(_settings.Endpoint);
var client = new VoucherService.VoucherServiceClient(binding, endpoint);

Binding:

private static BasicHttpBinding CreateBinding()
{
    var binding = new BasicHttpBinding
    {
        ReceiveTimeout = TimeSpan.FromMinutes(10),
        SendTimeout = TimeSpan.FromMinutes(10),
        MaxReceivedMessageSize = 33554432,
        TransferMode= TransferMode.Buffered,
        Security = new BasicHttpSecurity
        {
            Mode = BasicHttpSecurityMode.TransportCredentialOnly,
            Transport = new HttpTransportSecurity
            {
                ClientCredentialType = HttpClientCredentialType.Ntlm
            }
        }

    };
    binding.ReaderQuotas.MaxArrayLength = 32000;
    return binding;
}

and call:

var response = client.Send(/*some data*/)

There is old .net4 solution i took configuration from. And there it works and i can calls service but in new .net 6 solution with the same configuration i am receiving error like at the top. Can you suggest me anything i can check what else is missing? Thanks!

Answer 1

In .NET 6.0 and above, a Reference.cs file is usually generated after the WCF service is called.

In this file there is a self-generated method:

private static System.ServiceModel.Channels.Binding GetBindingForEndpoint(EndpointConfiguration endpointConfiguration)

My suggestion is to check if the configuration is the same as the WCF service.

Finally you use the parameterless constructor

var client = new VoucherService.VoucherServiceClient();