Mail Delivery Status Notification (Delay) from numerous addresses

Mail Delivery Status Notification (Delay) from numerous addresses

Hi there,

I am getting the following error message for emails I have attempted to send to gmail addresses as well as addresses on other sites (@matthewjohnsonphoto.com, @bomanistudios.com). Doesn't seem to be any rhyme or reason.

1—Can you resolve this problem? 

2—Will I receive a follow-up message to confirm whether/not these messages have in fact been delivered?

Note: I have x-ed out personal info on message below.

Thanks for any help.
Laura

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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, 05 Nov 2015 09:29:24 -0800 

----- The following addresses had fatal errors ----- 
[Status: Error, Address: < xxx@matthewjohnsonphoto.com>, ResponseCode 421, 4.7.0 Temporarily Deferred] 

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 1446741775129842.196081298299; Thu, 5 Nov 2015 08:42:55 -0800 (PST) 
Date:Thu, 05 Nov 2015 10:42:55 -0600 
From: xxx < xxx@intoquarterly.com> 
User-Agent:Zoho Mail 
Cc:"xxx" < xxx@intoquarterly.com> 
Subject:Re: Into Quarterly launch party: Nov. 19 
Content-Type:multipart/alternative; 
    boundary="----=_Part_7041_2116141416.1446741775053"

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