Web Service authentication

Hello
I have Web Service with two functions:

[Webmethod]
public string WinAuthHelloWorld()
{
return "WA : Hello world"
}

[Webmethod]
public string BasicAuthHelloWorld()
{
return "BA : Hello world"
}

In IIS I turn on the checkboxes "Integrated windows authentication" and "Basic Authentication".
In my client application I wrote:

// Main is static
static void Main()
{
Console.Write(CallBasicAuthHelloWorld());

Console.WriteCallWinAuthHelloWorld());
}

private string CallBasicAuthHelloWorld()
{
NetworkCredential netCredential = new NetworkCredential("domainname\username", "password");
Uri uri = new Uri(service.Url);
ICredentials credentials = netCredential.GetCredential(uri, "Basic");
service.Credentials = credentials;
service.PreAuthenticate = true;


return service.BasicAuthHelloWorld();
}

private string CallWinAuthHelloWorld()
{
Uri uri = new Uri(service.Url);
service.Credentials = = System.Net.CredentialCache.DefaultCredentials;

return WinAuthHelloWorld();
}

In invocation BasicAuthHelloWorld function I got Error 401 : Unauthorized.
What I dismiss in my code?

Thanks