Swift Mailer: Authentication required

Hi folks. Today I tried sending an email from a self hosted domain (not google or yahoo). This is my configuration:

'mailer' => [

 'class' => 'yii\swiftmailer\Mailer',

 'useFileTransport' => false, 

'transport' =>


             'class' => 'Swift_SmtpTransport', 

             'host' => 'mail.domain.com', 

             'username' => 'myemail@domain.com', 

             'password' => 'password',

             'port' => '587', // tried 465 with ssl and port 25 with tls

             'encryption' => 'tls'



The reported error is this one:

Expected response code 250 but got code 530, 530 5.7.0 Authentication required

What does authentication required means if Im sending the correct credentials?

This is from yii2-swiftmailer

Version 2.0.0

Are you able to send through that server with any kind of mail program/app?