SMTP error code : 551

com.sun.mail.smtp.SMTPSendFailedException: 551 This mail server requires authentication before sending mail from a locally hosted domain. Please reconfigure your mail client to authenticate before sending mail.

I am getting the error above when I integrate with the my Java Application running on a Tomcat server

Sending successfully if I use the same properties in separate class with main and run as java application

Why I am not getting this? Thank you in advance.


Finally got answer
Here we go: before it was like
`Properties props = new Properties();
props.put("", "");
props.put("mail.smtp.port", "25");
props.put("mail.smtp.starttls.enable", true);
props.put("mail.smtp.auth", true);`

now i changed to:
`Properties props = new Properties();
props.setProperty("", "");
props.setProperty("mail.smtp.port", "25");
props.setProperty("mail.smtp.starttls.enable", "true");
props.setProperty("mail.smtp.auth", "true");`