PHP Swift mailer: Failed to authenticate on SMTP using 2 possible authenticators

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 "[email protected]" using 2 possible authenticators

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

Answer 1

This might be old but somebody might get help through this. I too faced the same problem and received a mail on my gmail account stating that someone is trying to hack your account through an email client or a different site. THen I searched and found that doing below would resolve this issue.

Go to https://accounts.google.com/UnlockCaptcha‎ and unlock your account for access through other media/sites.

UPDATE : 2015

Also, you can try this, Go to https://myaccount.google.com/security#connectedapps At the bottom, towards right there is an option "Allow less secure apps". If it is "OFF", turn it on by sliding the button.

UPDATE : 2021

The google URL has now changed to : https://myaccount.google.com/lesssecureapps. You will be asked to relogin

Answer 2

I had the same issue, so I've disabled one setting on my WHM root login, which is as follows :

WHM > Home > Server Configuration > Tweak Settings > Restrict outgoing SMTP to root, exim, and mailman (FKA SMTP Tweak) [?]