Mail Delivery Status Notification (Delay)

Mail Delivery Status Notification (Delay)

I can not send to some recipients:

 This message was created automatically by mail delivery system.

THIS IS A WARNING MESSAGE ONLY.

YOU DO NOT NEED TO RESEND YOUR MESSAGE.

The original message was received at Thu, 10 Dec 2015 08:07:29 -0800
from carlos.tapia@avium.cl [carlos.tapia@avium.cl]

   ----- The following addresses had fatal errors -----    
  [Status: Error, Address: <pirrazabal@agricolaggk.cl>, ResponseCode 421, , Host not reachable.]

Message will be retried for 4 more day(s)