I have no idea how to solve the forwarding issue as below.
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Technical details of the failure:
dsn=5.0.0, stat=failure, 5.0.0 MailPolicy violation Error delivering to mailboxes
----- Transcript of session follows -----
Received:from e------v.---.local (mail.d----------.com.hk [118.xxx.xxx.198]) by mx.zohomail.com
with SMTPS id 1484015365095661.9408823836369; Mon, 9 Jan 2017 18:29:25 -0800 (PST)
Date:Tue, 10 Jan 2017 02:12:14 +0000
Subject:------------------------------------------------------
Content-Type:multipart/mixed;
boundary="_007_1490e8d5d23d4899b056752964186971e---------------local_"
P.S: Please note that your email forwarding will be disabled if there are too many failures.
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