There is one email account that we cannot send mails to any of the email addresses created under smrosen.com,au domain name.
Strange thing is all the other email accounts created under our account can send mails to smrosen.com.au without a problem.

We checked there was no any blocking being added from the smrosen.com.au mail server too.

We get this error every time we send the mails

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============ Forwarded message ============

From :mailer-daemon@mail.zoho.com

To : <sophieanne@partyaffairs.com.au>

Date : Tue, 01 Nov 2016 19:02:35 -0700

Subject : Undelivered Mail Returned to Sender

============ Forwarded message ============

 

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error.

 

steven@smrosen.com.au INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :Verification failed for <sophieanne@partyaffairs.com.au>

            No Such User Here"

            Sender verify failed

 

 

 

Received:from mail.zoho.com by mx.zohomail.com

    with SMTP id 1478052141563209.59462069678818; Tue, 1 Nov 2016 19:02:21 -0700 (PDT)

Message-ID:<15822c5d9f7.dacf4b2f759079.5063939348313429152@partyaffairs.com.au>

Date:Tue, 01 Nov 2016 19:02:21 -0700

From:Sophie Anne <sophieanne@partyaffairs.com.au>

User-Agent:Zoho Mail

To:"Steven Rosen(Steven)" <steven@smrosen.com.au>

Subject:Test - Please let me know if you receive this email

Content-Type:multipart/alternative;

    boundary="----=_Part_2364993_414585588.1478052141560"
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