Auto Email Sender software

Hello ,i am looking for a software that i can use for sending emails to mine customers once at a time and that goes directly to inbox, the software must be a windows software and developed in .Net or Delphi. I am in urgent need of this software so only providers those can provide me this in 2 day max can contact me: Requirements: Software must be able to use hotmail , yahoo, gmail and other free email services to send emails. Software must be able to add an email list once at a time to send emails.