Answer:

• If you got “Undeliverable Message”, you may read the error message in there.
  • If you do not understand the error message, you can contact us.
• If you do not get “Undeliverable Message”, it means the email has been successfully delivered to the receiver.
  • Please ask the receiver to check their Junk mailbox and email rules, or ask them to contact their own email administrator.
• If in doubt, you can send an email to your personal Gmail or Hotmail. Use this method to find out this is your problem or the receiver's problem.