Mandrill send email ruby on rails

Question

Im using mandrill for sending email and it show for some emails that the email From: ma@mail133-28.atl131.mandrillapp.com [mailto:ma@mail133-28.atl131.mandrillapp.com] On Behalf Of info@****.com

in my name mailer

default from: "info@****.com"

and in the development.rb

  config.action_mailer.raise_delivery_errors = true
  config.action_mailer.delivery_method = :letter_opener
  config.action_mailer.delivery_method = :smtp
  config.action_mailer.smtp_settings = {
    :address => "smtp.mandrillapp.com",
    :port => 587,
    :domain => 'www.****.com',
    :user_name => '**@**.ca',
    :password => '***',
    :authentication => :plain,
    :enable_starttls_auto => true 
  }

Why is that? i want to show from: info@****.com without this ma@mail133-28.atl131.mandrillapp.com [mailto:ma@mail133-28.atl131.mandrillapp.com] On Behalf Of info@****.com

Answer 1

From Mandrill KB

If your recipients use Outlook, Hotmail (and other Microsoft webmail services), or Gmail, they may see an indication in the email that it was sent by Mandrill on your behalf instead of just your 'from' name and address. Add SPF and DKIM records to your sending domains to remove the 'on behalf of' or 'via' information.

Instructions on how do that can be found here: https://mandrill.zendesk.com/hc/en-us/articles/205582277-How-do-I-add-DNS-records-for-my-sending-domains-