Connect to Microsoft Exchange specific folder using viewpoint gem. You can use owsap proxy if needed.

email_exchange.rb

require 'viewpoint'

class EmailExchange
  attr_accessor :folder_name
  def initialize username, password, ews_endpoint, exchange_folder_name, proxy
    if not (proxy.nil? or proxy.empty?)
        Viewpoint::EWS::EWS.set_trust_ca './owasp_zap_root_ca.pem'
    end
    Viewpoint::EWS::EWS.endpoint = ews_endpoint
    Viewpoint::EWS::EWS.set_auth username,password
    self.folder_name = exchange_folder_name
  end

  def get_body_of_inbox_folder_latest_email
    inbox = Viewpoint::EWS::Folder.get_folder_by_name(self.folder_name)
    if inbox.unread_count == 0
      return nil
    elsif inbox.unread_count == 1
      emails = inbox.todays_items
      unread_email = emails.find {|email| email.is_read? == false}
      unread_email.mark_read!
      return unread_email.body
    else
      return nil
    end
  end
  def check_mail
    check_mail_ten_times = 0
    email_body = nil
    while check_mail_ten_times <=10 do
      check_mail_ten_times = check_mail_ten_times + 1
      email_body = get_body_of_inbox_folder_latest_email
      if email_body != nil
        return email_body
      end
    end
    return email_body
  end
  def mark_all_as_read
    inbox = Viewpoint::EWS::Folder.get_folder_by_name(self.folder_name)
    if inbox.unread_count > 0
        emails = inbox.todays_items
        emails.each {|email| email.mark_read!}
    end
  end
end