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From: MAILER-DAEMON <>
To: kijitora@df.example.jp
Subject: Mail delivery failed
Message-Id: <e072e@df.example.jp>
Date: Tue, 11 Jun 2024 19:03:34 +0900
This is the DragonFly Mail Agent v0.13 at df.example.jp.
There was an error delivering your mail to <systemerror@libsisimai.net>.
mail-inbound.libsisimai.net [192.0.2.25] did not like our RCPT TO:
554 5.3.0 <systemerror@libsisimai.net>: Recipient address rejected: Internal system error. See https://libsisimai.org/en/reason/#systemerror
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Subject: Nyaan 01
To: <systemerror@libsisimai.net>
User-Agent: mail (GNU Mailutils 3.14)
Date: Tue, 11 Jun 2024 19:03:34 +0900
Message-Id: <666820f6.e072c.44bd3f67@df.example.jp>
From: <kijitora@df.example.jp>