Web Service 401: Unauthorized Error
// Webservice
        IdentityService ws = new IdentityService();

        // Test Static Credentials
        string username = "twfnf";
        string password = "testme99";
        string domain = "testapps1";

        NetworkCredential credentials = new NetworkCredential(username, password, domain);

        CredentialCache credCache = new CredentialCache();
        credCache.Add(new Uri(ws.Url), "Basic", credentials);

        ws.Credentials = credCache;
        ws.PreAuthenticate = true;
        ws.AuthenticateUser();

CredentialCache credCache = new CredentialCache();
credCache.Add(new Uri(ws.Url), "Basic", credentials);

// Webservice
    IdentityService ws = new IdentityService();

    // Test Static Credentials
    string username = "twfnf";
    string password = "testme99";
    string domain = "testapps1";

    NetworkCredential credentials = new NetworkCredential(username, password, domain);

    ws.Credentials = credentials;
    ws.PreAuthenticate = true;
    ws.AuthenticateUser();