One of my colleague can't receive some e-mails, while receives the others.

This message is just from one sender, she has more people who can't send to her.

Pls help! 

Thanks!

Karoly

-----Original Message-----
From: Mail Delivery System [mailto: Mailer-Daemon@s20-2.mediacenter.hu ]
Sent: Thursday, December 8, 2016 2:40 PM
To:  gyula.t@tiens.hu
Subject: Mail delivery failed: returning message to sender

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. The following address(es) failed:

   anna@tiensdebrecen.hu
    SMTP error from remote mail server after RCPT
TO:< anna@tiensdebrecen.hu >:
    host  mx.zoho.com  [204.141.32.121]: 541 5.4.1 Mail rejected by
destination domain

------ This is a copy of the message, including all the headers. ------

Return-path: < gyula.t@tiens.hu >
Received: from  business-89-135-189-81.business.broadband.hu  ([89.135.189.81]
helo=TarrGyulaPC)
        by  s20-2.mediacenter.hu  with esmtpa (Exim 4.80)
        (envelope-from < gyula.t@tiens.hu >)
        id 1cEyv0-0001Ca-MI
        for  anna@tiensdebrecen.hu ; Thu, 08 Dec 2016 14:39:26 +0100
From: "Tarr Gyula" < gyula.t@tiens.hu >
To: =?iso-8859-2?B? J0LtcvMgQW5uYSc=?= < anna@tiensdebrecen.hu >
Subject: =?iso-8859-2?B?cHLzYmE=?=
Date: Thu, 8 Dec 2016 14:39:28 +0100
Message-ID: <001701d25158$7f9ea140$ 7edbe3c0$@ tiens.hu >
MIME-Version: 1.0
Content-Type: multipart/related;
        boundary="----=_NextPart_000_ 0018_01D25160.E163F3A0"
X-Mailer: Microsoft Outlook 16.0
Thread-Index: AdJRWH95fGPcg+8/RCK+ yZWQ6KGHSw==
Content-Language: hu

This is a multipart message in MIME format.

------=_NextPart_000_0018_ 01D25160.E163F3A0
Content-Type: multipart/alternative;
        boundary="----=_NextPart_001_ 0019_01D25160.E163F3A0"


------=_NextPart_001_0019_ 01D25160.E163F3A0
Content-Type: text/plain;
        charset="iso-8859-2"
Content-Transfer-Encoding: quoted-printable [...]