아래처럼 메일이 발송되는데 내부 테스트시에는 문제 없었어서... 혹시 왜이럴까요?

Hi. This is the qmail-send program at ruwa64-005.fmcity.com. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out.

: Connected to 66.96.140.73 but greeting failed. Remote host said: 554 bosimpinc14 bizsmtp  Connection rejected. Reverse DNS for 220.73.161.15 does not exist. I'm not going to try again; this message has been in the queue too long.

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Return-Path: <id@naver.com> Received: (qmail 25773 invoked by uid 508); 27 Nov 2018 11:34:16 +0900 Received: from unknown (HELO url) (127.0.0.1)   by cafe24.com with SMTP; 27 Nov 2018 11:34:16 +0900 Date: Tue, 27 Nov 2018 11:34:16 +0900 To: admin@domain.com From: =?UTF-8?B?67mh7J20?= <id@naver.com> Subject: =?UTF-8?B?W+2GoOuLiOyKiOyWtCDqs7Xsi53sgqzsnbTtirhdIOu5oeydtCDri5jqu5g=?=  =?UTF-8?B?7IScIO2ajOybkOycvOuhnCDqsIDsnoXtlZjshajsirXri4jri6Qu?= Message-ID: <191465833f7652905f8b2dbf71f60912@urlr> X-Mailer: PHPMailer 5.2.22 (https://github.com/PHPMailer/PHPMailer) MIME-Version: 1.0 Content-Type: multipart/alternative;     boundary="b1_191465833f7652905f8b2dbf71f60912" Content-Transfer-Encoding: 8bit

This is a multi-part message in MIME format.

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회원가입 알림 메일                               oooo 공식사이트                               ooo 님께서 회원가입 하셨습니다.             회원 아이디 : ooo             회원 이름 : ooo             회원 닉네임 : ooo             추천인아이디 :                  관리자에서 회원정보 확인하기

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