Fatal error:  Uncaught exception 'Swift_TransportException' with message 'Failed to authenticate on SMTP server with username "

1844905601@qq.com" using 1 possible authenticators' in D:\www\test\muke\pdo\class\app2\swiftmailer-master\lib\classes\Swift\Transport\Esmtp\AuthHandler.php:184 Stack trace: #0 D:\www\test\muke\pdo\class\app2\swiftmailer-master\lib\classes\Swift\Transport\EsmtpTransport.php(312): Swift_Transport_Esmtp_AuthHandler->afterEhlo(Object(Swift_SmtpTransport)) #1 D:\www\test\muke\pdo\class\app2\swiftmailer-master\lib\classes\Swift\Transport\AbstractSmtpTransport.php(120): Swift_Transport_EsmtpTransport->_doHeloCommand() #2 D:\www\test\muke\pdo\class\app2\swiftmailer-master\lib\classes\Swift\Mailer.php(80): Swift_Transport_AbstractSmtpTransport->start() #3 D:\www\test\muke\pdo\class\app2\doAction.php(52): Swift_Mailer->send(Object(Swift_Message)) #4 {main}  thrown in D:\www\test\muke\pdo\class\app2\swiftmailer-master\lib\classes\Swift\Transport\Esmtp\AuthHandler.php on line 184

老师请问这什么问题?发送不了邮件