title: How to use user name and password in AUTH PLAIN?
body: <p>I am trying to send Email using telnet and smtp.mail.yahoo.com server. when I try to authenticate myself on server using my yahoo mail ID and password. the server gave me Error;</p>
  
  <pre><code>501 malformed auth input (#5.5.4)
  </code></pre>
  
  <p>I am using AUTH PLAIN mechanism. I don't know how to combine user name and password. And after that convert it to base64 and then send.  </p>
  
  <p>Can somebody suggest me how to combine user name and password for AUTH PLAIN? Thanks</p>