action mailer error to deliver email

I am trying implementing send mail through action mailer in rails related code are..

my mailers/user_mailer.rb

          class UserMailer < ActionMailer::Base
    default :from => "bkdebasish90@gamil.com"
     def registration_confirmation(user)
        mail(:to=>user.email, :subject =>"Registered")
        end
        end

users.controller is

  def create
     @user = User.new(user_params)
        respond_to do |format| 
    if @user.save
    UserMailer.registration_confirmation(@user).deliver
      format.html { redirect_to @user, notice: 'User was successfully   created.' }
       format.json { render :show, status: :created, location: @user }
      else
     format.html { render :new }
    format.json { render json: @user.errors, status: :unprocessable_entity }
   end
   end
  end  

Here, Your initializer\setup_mail.rb setting will go to the development.rb

    config.action_mailer.default_url_options = { host: 'localhost', port: 9292 }

    config.action_mailer.delivery_method = :smtp
      config.action_mailer.smtp_settings = {
        :address     =>"smtp.thejaingroup.com",
         :domain      =>"thejaingroup.com",
         :port        => 587,
       :user_name   =>"debasish@thejaingroup.com",
        :password    =>"************"
        :authentication =>"plain"
       }

and my view is .. user_registration.text.erb ---is

            Hi sir you successfully Completed signed..........!

my have a error msg after running this apps.. SocketError in UsersController#create getaddrinfo: The requested name is valid, but no data of the requested type was found.