ArgumentError: SMTP-AUTH requested but missing user name + ActionMailer

Question

I m not able to sent mail using actionmailer everytime I try to deliver the mail using actionmailer It report me with error

ArgumentError: SMTP-AUTH requested but missing user name

This is Strange as I'm able to sent mail via Telnet but not using ActionMailer

Attaching Telnet Screenshot

Here my SMTP settings

config.action_mailer.delivery_method = :smtp

config.action_mailer.smtp_settings = {
    :address => '216.224.183.100',
    :port                 => 25,
    :domain               => '[domain_name]',
    :username             => "[username]",
    :password             => "[password]",
    :authentication       => 'plain',
   :enable_starttls_auto => true
 }

Can anyone Please tell as to via the Mail is not getting sent

Answer 1

Got it. It's user_name, and not username.