title: Nodemailer is not able send mail using gmail
body: <p>I am trying to send email through <strong>nodemailer</strong> but is not able to send email and showing following error.</p>
  
  <pre><code>{ [Error: Invalid login]
    code: 'EAUTH',
    response: '534-5.7.14 &lt;https://accounts.google.com/ContinueSignIn?sarp=1&amp;scc=1&amp;plt=AKgnsbsTr\n534-5.7.14 2r0PE8hXz57GMK9aydA3GouUGQr1Pc2wBywEf6i09kKVOv9Qv5y9Csy_lL-PIgUO6ML8uA\n534-5.7.14 ZsEiEkpAU0N5aiQBZdI1urKo3XfCiiS2MhjiUZaBgpn88sFXR-sBeA5ydMc_Md1F5wDcbX\n534-5.7.14 7ynrcVC-h0H_-e_ptvGhA3ywiHOSoDZAxzrindvEMNkXmCilbo9J7ITdlXFKwQjITaIkei\n534-5.7.14 Tk8QMKEY22ldNjE78Lh2ekheLd5M&gt; Please log in via your web browser and\n534-5.7.14 then try again.\n534-5.7.14  Learn more at\n534 5.7.14  https://support.google.com/mail/answer/78754 21sm9309692qgj.21 - gsmtp',
    responseCode: 534 }
  </code></pre>
  
  <p>I am using exact code as shown in nodemailer documentation.</p>
  
  <p>this is server side code which i am using.</p>
  
  <pre><code>var transporter = nodemailer.createTransport({
      service: 'Gmail',
      auth: {
         user: 'username',
         pass: 'password'
      }
  });
  
  app.post('/sendfeedbackmail', function(req, res) {
  
      var mailOptions = {
          from: 'Feedback&lt;username@gmail.com&gt;', // sender address 
          to: 'user1@gmail.com', // receiver 
          subject: 'Subject', // Subject line 
          text: mailData, // plaintext body 
          html: mailData // html body 
      };
  
     // send mail with defined transport object 
     transporter.sendMail(mailOptions, function(error, info) {
         if (error) {
            console.log(error);
            res.send({success:false});
         }else{
             res.send({
                success: true
             })
         }
     });
  })
  </code></pre>
  
  <p>This was working fine few days ago and still working fine for other email client then gmail hence i think the issue may be related to any security setting of gmail account.</p>