private void cmdTest_Click(object sender, EventArgs e)
    {

        Uri uriLogin = new Uri("http://feverclan.com/forums/login.php?do=login");
        StringBuilder data = new StringBuilder();
        data.Append("vb_login_username=" + txtUsername.Text + "&vb_login_password=" + txtPassword.Text
                            + "securitytoken=guest&"
                            + "cookieuser=checked&"
                            + "do=login");

        HttpWebRequest login = HttpWebRequest.Create(uriLogin) as HttpWebRequest;
        login.CookieContainer = cookieContainer;
        login.Method = WebRequestMethods.Http.Post;
        login.ContentLength = data.Length;
        login.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:47.0) Gecko/20100101 Firefox/47.0";
        login.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
        login.ContentType = "text/html; charset=ISO-8859-1";
        StreamWriter writer = new StreamWriter(login.GetRequestStream());
        writer.Write(data);
        writer.Close();
        login.GetResponse();
        HttpWebResponse response = login.GetResponse() as HttpWebResponse;
        foreach (Cookie c in response.Cookies)
        {
            cookieContainer2.Add(c);
        }
        StreamReader reader = new StreamReader(response.GetResponseStream());
    }