PHP Swift mailer: Failed to authenticate on SMTP u

Question

When I send an email with the PHP Swift mailer to this server: smtp.exchange.example.com like this:

// Load transport
$this->transport =
    Swift_SmtpTransport::newInstance(
       self::$config->hostname,
       self::$config->port
    )
    ->setUsername(self::$config->username)
    ->setPassword(self::$config->password)
    ;

// Load mailer
$this->mailer = Swift_Mailer::newInstance($this->transport);

// Initialize message
$this->message = Swift_Message::newInstance();

// From
$this->message->setFrom(self::$config->from);

// Set message etc. ...

// Send
$this->mailer->send($this->message);

I get a strange error back:

Failed to authenticate on SMTP server with username "[e-mail]" using 2 possible authenticators

I know for sure that the login-info is correct.

Answer 1

try putting username in double quote "username", somehow that fixed for me.

Answer 2

If you are trying to send mail from your local enviroment eg. XAMPP or WAMP, this error will occur everytime, go ahead and try the same code on your web hosting or whatever you are using for production.

Also, 2 step authentication from google may be the issue.

Answer 3

First check if there is any connectivity problem and you can reach the SMTP server:

In terminal type:

telnet servername portnumber 

If you receive the 220 response you can reach the SMTP server and there is no connectivity problem but if the connection to the server failed see what's wrong in your network.

If the server needs auth try to authenticate on the server by username and password and see if something goes wrong.

At last see if the server requires encryption and if yes openssl and other stuff are configured correctly.

Answer 4

I just received the same error.

The strange thing is that commented the credential lines

// ->setUsername(self::$config->username)
// ->setPassword(self::$config->password)

And the problem disappeared.

I'm puzzled because the mail server definitely needs those credentials.

Answer 5

I got the same same error.

I was using gmail account and Google's SMTP server to send emails. The problem was due to SMTP server refusing to authorize as it considered my web host (through whom I sent email) as an intruder.

I followed Google's process to identify my web host as an valid entity to send email through my account and problem was solved.

Answer 6

The server might require some kind of encryption and secure authentication.
see http://swiftmailer.org/docs/sending.html#encrypted-smtp