SMTP error code : 551

javax.mail,javax.activation

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