How to configure gmail smtp and phpmailer? - php

Question

I want to know where the problem is because I get authentication error.
I already have a few gmail accounts,
I created a new one for my website,
I added a new email in "Account and import" to my old gmail account.
I copied my new email username and password to phpmailer code
include_once('phpmailer/class.phpmailer.php');
include_once('phpmailer/class.smtp.php');
//6nb5Drv;
function sendmail(){
$mail = new PHPMailer();
$mail->IsSMTP(); // set mailer to use SMTP
$mail->SMTPAuth = true; // turn on SMTP authentication
$mail->SMTPSecure = "tls";
$mail->Host = "smtp.gmail.com"; // specify main and backup server
$mail->Port = 587; // Set the SMTP port i tried and 457
$mail->Username = 'newmail#gmail.com'; // SMTP username
$mail->Password = 'newmailpass'; // SMTP password
$mail->SMTPDebug = 1; // enables SMTP debug information (for testing)
// 1 = errors and messages
// 2 = messages only
$mail->From = 'from#yahoo.com';
$mail->FromName = 'From';
$mail->AddAddress('to#gmail.com', 'To'); // Add a recipient
$mail->IsHTML(true); // Set email format to HTML
$mail->Subject = 'Here is the subject';
$mail->Body = 'This is the HTML message body <strong>in bold!</strong>';
$mail->AltBody = 'This is the body in plain text for non-HTML mail clients';
if(!$mail->Send()) {
echo 'Message could not be sent.';
echo 'Mailer Error: ' . $mail->ErrorInfo;
exit;
}
echo 'Message has been sent';
}
sendmail();
But I get an authentication error.
What is wrong?
Probably something with the credentials, how do I configure gmail smtp?
Debug report:
2015-12-04 17:56:15 CLIENT -> SERVER: EHLO www.site.co
2015-12-04 17:56:15 CLIENT -> SERVER: STARTTLS 2015-12-04
17:56:15 CLIENT -> SERVER: EHLO www.site.co 2015-12-04
17:56:15 CLIENT -> SERVER: AUTH LOGIN 2015-12-04 17:56:15 CLIENT ->
SERVER: UHJlZGljdG9sb2d5 2015-12-04 17:56:15 CLIENT -> SERVER:
U2dHZlB0VHZUbTZ1SW9ZMi1qTlNCQQ== 2015-12-04 17:56:17 SMTP ERROR:
Password command failed: 435 4.7.8 Error: authentication failed:
UGFzc3dvcmQ6 2015-12-04 17:56:17 SMTP Error: Could not authenticate.
2015-12-04 17:56:17 CLIENT -> SERVER: QUIT 2015-12-04 17:56:17 SMTP
connect() failed.
https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting Message
could not be sent.Mailer Error: SMTP connect() failed.
https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

Answer 1

According to this post:
PHPMailer - SMTP ERROR: Password command failed when send mail from my server, in some case, you have to specify google that this is not a suspicious activity and activate some less secure option in your account.
Assuming this is the right password...