Не передаются cookies (secure?) авторизация на mail.ru - C#

public static void Main()
       {

           string url = "https://auth.mail.ru/cgi-bin/auth";           
           string Data = "Domain=mail.ru&Login=free_lsd&Password=YYY&new_auth_form=1&saveauth=1";
           CookieContainer cookies = new CookieContainer();
           string cook;
 
           //HttpWebRequest  req = (HttpWebRequest)WebRequest.Create("https://mail.ru");
           /*
           req.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/43.0.2357.134 Safari/537.36";
           //req.Referer = "https://auth.mail.ru/cgi-bin/auth?from=splash";
           //req.Method = "GET";
           //req.CookieContainer = cookies;
         
           req.KeepAlive = true;
           //req.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*//*;q=0.8";
           req.Headers.Add("Accept-Language", "ru-RU,ru;q=0.8,en-US;q=0.6,en;q=0.4");
           */ 
 
           //HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
 
           HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
           req.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/43.0.2357.134 Safari/537.36";
           req.Method = "POST";
           req.Timeout = 10000;
           req.Referer = "https://mail.ru/?from=logout&ref=main";
           req.ContentType = "application/x-www-form-urlencoded";
           req.CookieContainer = cookies;
           
           req.KeepAlive = true;
           req.Headers.Add("Accept-Language", "ru-RU,ru;q=0.8,en-US;q=0.6,en;q=0.4");
           req.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8";
           //req.Headers.Add("Accept-Encoding", "gzip, deflate, sdch");
                     
           byte[] SentData = Encoding.GetEncoding(1251).GetBytes(Data);
           req.ContentLength = SentData.Length;
           Stream SendStream = req.GetRequestStream();
           SendStream.Write(SentData, 0, SentData.Length);
           SendStream.Close();
           HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
           Stream ReceiveStream = resp.GetResponseStream();
           StreamReader sr = new StreamReader(ReceiveStream, Encoding.UTF8);
           char[] read = new char[256];
           int count = sr.Read(read, 0, 256);
           string Out = String.Empty;
           while (count > 0)
           {
               String str = new String(read, 0, count);
               Out += str;
               count = sr.Read(read, 0, 256);
           }
 
           cook = string.Empty;
           foreach (Cookie c in resp.Cookies)
           {
               cook += c + "\r\n";
           }
           Console.WriteLine(cook);
 
           //cookies = resp.CookieContainer;
           //Console.WriteLine(resp.Headers);
           StreamWriter OutFile = new StreamWriter("C:\\Users\\alex\\Desktop\\out.html");
           OutFile.Write(Out);
           OutFile.Close();

           //req = (HttpWebRequest)WebRequest.Create("https://auth.mail.ru/sdc?from=https%3A%2F%2Fe.mail.ru%2Fmessages%2Finbox%2F%3Fback%3D1");
           HttpWebRequest req2 = (HttpWebRequest)WebRequest.Create("https://e.mail.ru/messages/inbox/?back=1");
           req2.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/43.0.2357.134 Safari/537.36";
           req2.Referer = "https://auth.mail.ru/cgi-bin/auth?from=splash";
           req2.Method = "GET";
           req2.CookieContainer = cookies;

           Console.WriteLine();
           //Console.Read();
 
           req2.KeepAlive = true;
           req2.Headers.Add("Accept-Language", "ru-RU,ru;q=0.8,en-US;q=0.6,en;q=0.4");
           req2.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8";
           //req.Headers.Add("Accept-Encoding", "gzip, deflate, sdch");
           //req.AllowAutoRedirect = false;
           //req.Headers.Add(resp.Headers["Set-Cookie"].ToString());
 
           resp = (HttpWebResponse)req2.GetResponse();
           sr = new StreamReader(resp.GetResponseStream());
           Out = sr.ReadToEnd();
           //Console.WriteLine(Out);
           OutFile = new StreamWriter("C:\\Users\\alex\\Desktop\\out.html");
           OutFile.Write(Out);
           OutFile.Close();
 
           cook = string.Empty;
           foreach (Cookie c in resp.Cookies)
           {
               cook += c + "\r\n";
           }
           Console.WriteLine(cook);

           Console.WriteLine();
           Console.Read();
           /*
           string url = "http://mail.ru";
           HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
           HttpWebResponse response = (HttpWebResponse )request.GetResponse();
           Stream stream = response.GetResponseStream();
           StreamReader sr = new StreamReader(stream);
           string Out = sr.ReadToEnd();
           sr.Close();
           //Console.WriteLine(Out);
           //Console.Read();
           StreamWriter srOut = new StreamWriter("C:\\Users\\alex\\Desktop\\out.html");
           srOut.Write(Out);
           srOut.Close();
           return;
           */
       }