Я могу подключиться к серверу Yahoo SMTP, но не к серверу Gmail

У меня есть простой почтовый клиент SMTP. Я могу отправить электронное письмо, используя это приложение и мой почтовый аккаунт Yahoo. Но когда я собираюсь отправить электронное письмо, используя мою учетную запись Gmail, подключение к SMTP-серверу Google не удается!
Вот мой класс SMTP:

Smtp::Smtp( const QString &user, const QString &pass, const QString &host, int port, int timeout )
{
socket = new QSslSocket(this);

connect(socket, SIGNAL(readyRead()), this, SLOT(readyRead()));
connect(socket, SIGNAL(connected()), this, SLOT(connected() ) );
connect(socket, SIGNAL(error(QAbstractSocket::SocketError)), this,SLOT(errorReceived(QAbstractSocket::SocketError)));
connect(socket, SIGNAL(stateChanged(QAbstractSocket::SocketState)), this, SLOT(stateChanged(QAbstractSocket::SocketState)));
connect(socket, SIGNAL(disconnected()), this,SLOT(disconnected()));this->user = user;
this->pass = pass;

this->host = host;
this->port = port;
this->timeout = timeout;}

void Smtp::sendMail(const QString &from, const QString &to, const QString &subject, const QString &body)
{
// qDebug() << subject<<" ::: "<<body;
message = "To: " + to + "\n";
message.append(QString("From: " + from + "\n"));
message.append("Subject: " + subject + "\n");
message.append(body);

message.replace( QString::fromLatin1( "\n" ), QString::fromLatin1( "\r\n" ) );
message.replace( QString::fromLatin1( "\r\n.\r\n" ),
QString::fromLatin1( "\r\n..\r\n" ) );
//qDebug()<<message;
this->from = from;
rcpt = to;
state = Init;
socket->connectToHostEncrypted(host, port); //"smtp.gmail.com" and 465 for gmail TLS
if (!socket->waitForConnected(timeout)) {
qDebug() << socket->errorString();
}

t = new QTextStream( socket );
t->setCodec("UTF-8");
}

Smtp::~Smtp()
{
delete t;
delete socket;
}
void Smtp::stateChanged(QAbstractSocket::SocketState socketState)
{

qDebug() <<"stateChanged " << socketState;
}

void Smtp::errorReceived(QAbstractSocket::SocketError socketError)
{
qDebug() << "error " <<socketError;
}

void Smtp::disconnected()
{

qDebug() <<"disconneted";
qDebug() << "error "  << socket->errorString();
}

void Smtp::connected()
{
qDebug() << "Connected ";
}

void Smtp::readyRead()
{

qDebug() <<"readyRead";
// SMTP is line-oriented

QString responseLine;
do
{
responseLine = socket->readLine();
response += responseLine;
}
while ( socket->canReadLine() && responseLine[3] != ' ' );

responseLine.truncate( 3 );

qDebug() << "Server response code:" <<  responseLine;
qDebug() << "Server response: " << response;

if ( state == Init && responseLine == "220" )
{
// banner was okay, let's go on
*t << "EHLO localhost" <<"\r\n";
t->flush();

state = HandShake;
}
//No need, because I'm using socket->startClienEncryption() which makes the SSL handshake for you
/*else if (state == Tls && responseLine == "250")
{
// Trying AUTH
qDebug() << "STarting Tls";
*t << "STARTTLS" << "\r\n";
t->flush();
state = HandShake;
}*/
else if (state == HandShake && responseLine == "250")
{
socket->startClientEncryption();
if(!socket->waitForEncrypted(timeout))
{
qDebug() << socket->errorString();
state = Close;
}//Send EHLO once again but now encrypted

*t << "EHLO localhost" << "\r\n";
t->flush();
state = Auth;
}
else if (state == Auth && responseLine == "250")
{
// Trying AUTH
qDebug() << "Auth";
*t << "AUTH LOGIN" << "\r\n";
t->flush();
state = User;
}
else if (state == User && responseLine == "334")
{
//Trying User
qDebug() << "Username";
//GMAIL is using XOAUTH2 protocol, which basically means that password and username has to be sent in base64 coding
//https://developers.google.com/gmail/xoauth2_protocol
*t << QByteArray().append(user).toBase64()  << "\r\n";
t->flush();

state = Pass;
}
else if (state == Pass && responseLine == "334")
{
//Trying pass
qDebug() << "Pass";
*t << QByteArray().append(pass).toBase64() << "\r\n";
t->flush();

state = Mail;
}
else if ( state == Mail && responseLine == "235" )
{
// HELO response was okay (well, it has to be)

//Apperantly for Google it is mandatory to have MAIL FROM and RCPT email formated the following way -> <[email protected]>
qDebug() << "MAIL FROM:<" << from << ">";
*t << "MAIL FROM:<" << from << ">\r\n";
t->flush();
state = Rcpt;
}
else if ( state == Rcpt && responseLine == "250" )
{
//Apperantly for Google it is mandatory to have MAIL FROM and RCPT email formated the following way -> <[email protected]>
*t << "RCPT TO:<" << rcpt << ">\r\n"; //r
t->flush();
state = Data;
}
else if ( state == Data && responseLine == "250" )
{

*t << "DATA\r\n";
t->flush();
state = Body;
}
else if ( state == Body && responseLine == "354" )
{

*t << message << "\r\n.\r\n";
t->flush();
state = Quit;
}
else if ( state == Quit && responseLine == "250" )
{

*t << "QUIT\r\n";
t->flush();
// here, we just close.
state = Close;
emit status( tr( "Message sent" ) );
}
else if ( state == Close )
{
deleteLater();
return;
}
else
{
// something broke.
QMessageBox::warning( 0, tr( "Qt Simple SMTP client" ), tr( "Unexpected reply from SMTP server:\n\n" ) + response );
state = Close;
emit status( tr( "Failed to send message" ) );
}
response = "";
}

я использую smtp.mail.yahoo.com как Yahoo SMTP-сервер и smtp.gmail.com в качестве сервера SMTP Gmail. Я использую порт 465 для обоих.
Вот вывод отладки (хотя я думаю, что это бесполезно):

stateChanged  QAbstractSocket::HostLookupState
stateChanged  QAbstractSocket::ConnectingState
stateChanged  QAbstractSocket::UnconnectedState
error  QAbstractSocket::SocketTimeoutError
stateChanged  QAbstractSocket::UnconnectedState
"Socket operation timed out"

я использую Windows 7 64-битная . Qt 4.8.5 и visual studio 2008 !