title: SMTP authentication failure while using SendGrid/Gmail
body: <p>I am getting SMTP Authentication Failure on the server and the mail is getting send via the server SMTP only... </p>
  
  <p>It appears to be a server configuration or related problem, but I am not sure.</p>
  
  <p>This is the debug details:</p>
  
  <pre><code>250-SIZE 52428800
  250-8BITMIME
  250-PIPELINING
  250-AUTH PLAIN LOGIN
  250-STARTTLS
  250 HELP
  
  Failed to authenticate password. Error: 535 Incorrect authentication data
  
  from: 250 OK
  
  to: 250 Accepted
  
  data: 354 Enter message, ending with "." on a line by itself
  
  250 OK id=1U8Pjp-0002As-FB
  
  quit: 221 ************** closing connection
  
  Your message has been successfully sent using the following protocol: smtp
  </code></pre>
  
  <p>While testing from my local system, this works and the email is being sent via sendgrid.me</p>
  
  <p>Again, This may not be a SendGrid Problem, but if you have faced similar issue, Can you please tell me what is the problem here? </p>
  
  <p>I am using CentOs and I have cPanel in the server. I believe we are using EXIM for mail server.</p>