메일이 받아지지 않습니다

내부 메일들끼리는 주고받고가 되는데.. netian.com yahoo.co.kr 등 외부메일들이 제게로 메일을 보내면.. 제가 받을 수가 없어요
여러번 보냈다고 하는데요

그사람들에게 물어보니
아래와 같은 리텐메일이 왔다고 합니다


네띠앙이용자는,
==================================================
Message from yahoo.com.
Unable to deliver message to the following address(es).

<****@****>:
211.43.212.217 does not like recipient.
Remote host said: 553 sorry, that domain isn't in my list of allowed
rcpthosts (#5.7.1)
Giving up on 211.43.212.217.
==================================================



야후이용자는,
==================================================
- These recipients of your message have been processed by the mail server:

****@****; Action: Failed; Status: 5.1.3 (bad destination mailbox address syntax)
Remote MTA mail.uhanmold.co.kr: SMTP diagnostic: 553 sorry, that domain isn't in my list of allowed rcpthosts (#5.7.1)
==================================================

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