Error sending email: server Answer: 550 5.7.1 Must Authenticate

Question

I’m trying to use the function mail() of However, the following warning appears when I run the script:

" Warning: mail() [Function.mail]: SMTP server Answer: 550 5.7.1 Must Authenticate!"

How do I set this up?

Follows the code:

$message = "Blablablablablablabla";

// In case any of our lines are larger than 70 characters, we should use wordwrap()

$message = wordwrap($message, 70);

// Send

mail('[email protected]', 'Solicitação de Cadastro de Fornecedor de Serviço - Numero - 111 - Controladoria - Marco Projetos e Construções', $message);

Answer 1

To prevent email abuse, better known as SPAM, many servers require the client to be authenticated and legitimate.

The function mail() cannot perform this authentication, so it is necessary to use another library that supports SMTP authentication. (PEAR Mail, phpmailer, Swift Mailer, etc)

If you have an interest, recommend that great tutorial to use Phpmailer.

Source Fonte2

Answer 2

Some servers do not allow the field from email is omitted. It is configured as the fourth argument of the mail function.

Configure it as follows:

$headers = 'From: [email protected]' . PHP_EOL;
mail('[email protected]', 'titulo', $message, $headers);

Answer 3

You have to build and send the headers of your email:

    $headers  = 'From: [email protected]'."\r\n";
    $headers .= 'Reply-To: [email protected]'."\r\n";
    $headers .= 'MIME-Version: 1.0'."\n";
    $headers .= 'Content-type: text/html; charset=UTF-8'."\r\n";

    if(mail('[email protected]', 'Solicitação de Cadastro de Fornecedor de Serviço - Numero - 111 - Controladoria - Marco Projetos e Construções', $message, $headers)) 
        echo "Email enviado";
    else 
        echo "Ocorreu um erro no envio do email!";