title: Using nodemailer and smtp send mail without authentication
body: <p>Below is my code. This works fine with <strong>gmail smtp server</strong>.
  But when I use my office one (which does not require authentication) it fails</p>
  <p>May be the syntax I am using is wrong.</p>
  <p>below is the code working with gmail smtp:</p>
  <pre><code>
      var mailOptions = {
          from: 'xxxx@abcd.com',
          to: 'xxxxyy@abcd.com',
          subject: 'hello world!',
          html: '&lt;img src=&quot;cid:logo&quot;&gt;',
          attachments: [{
              filename: 'test.png',
              path: 'D:/bbbbb/mmmm/src/test.png',
              cid: 'logo' //same cid value as in the html img src
          }]
      };
  
      transport.sendMail(mailOptions, (error, info) =&gt; {
          if (error) {
              console.log(error);
          }
          console.log(`Message sent: ${info.response}`);
      }); 
  
  </code></pre>
  <p>As Our company <code>smtp</code> does not require authentication,
  I have tried below code:</p>
  <pre><code> var transport = nodemailer.createTransport(&quot;smtps://xxxx@abcd.com:&quot;+encodeURIComponent('') + &quot;@xxxx.xxxrxx.com:25&quot;);
  </code></pre>
  <p>OR</p>
  <pre><code>var transport = nodemailer.createTransport(&quot;smtps://xxx.xxx.com:25&quot;);
  </code></pre>
  <p>but all resulted error</p>
  <pre><code>{ Error: 101057795:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:openssl\ssl\s23_clnt.c:797:
  
  at Error (native) code: 'ECONNECTION', command: 'CONN' }
  </code></pre>
  <p>My guess is syntax is wrong.
  Can some one pls correct me</p>
  <p>Thanks and Regards.</p>