Help! Mail Delivery Status Notification

Help! Mail Delivery Status Notification

Hola.
Intento enviar un e-mail a mis contactos pero me figura este error:

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 Tue, 03 Jan 2017 13:05:25 -0800
from m*********@*******.com.ar [ m*********@*******.com.ar]

----- The following addresses had fatal errors -----
[Status: Error, Address: <********* @hotmail.com>, ResponseCode 421, RP-001 (SNT004-MC9F12) Unfortunately, some messages from 135.84.**.*** weren't sent. Please try again. We have limits for how many messages can be sent per hour and per day. You can also refer to http://mail.live.com/mail/troubleshooting.aspx#errors.]

Message will be retried for 4 more day(s)

----- Transcript of session follows -----

Received:from mail.zoho.com by mx.zohomail.com
    with SMTP id 14834748*******************433307241; Tue, 3 Jan 2017 12:20:13 -0800 (PST)
Message-ID:<15965fd4217.12526 6246157644.132***************45@***.com.ar>
Date:Tue, 03 Jan 2017 20:20:13 +0000
From:M***************** < m****@*******.com.ar>
User-Agent:Zoho Mail
To:"Carlos Carli" < e*****@hotmail.com>
Subject:Fwd: C
Content-Type:multipart/mixed;
    boundary="----=_Part_488278_514732172.1483474813468"


Lo que pasó hace unos d`´ias fue que intentamos enviar un mail a todsos nuestros contactos para desearles felices fiestes. Yo interpreto que ahora nos toman como spam y NO ES ASí.

Por favor necesito solucionarlo ya que trabajo con este gran servicio de e-mail.

Espero respuestas.