The letter goes to spam on yandex.ru, what's the problem?

Question

Email

I send the letter from all SMTP. with mail.ru everything is fine, on Yandex it is spam, there is a property of a letter with yandex
-------------------------
Received: from mxfront1j.mail. yandex.net ([127.0.0.1])
by mxfront1j.mail.yandex.net with LMTP id jXa9aPM7
for ; Tue, 11 Apr 2017 11:43:10 +0300
Received: from germovvod.pw (germovvod.pw [146.185.154.178])
by mxfront1j.mail.yandex.net (nwsmtp/Yandex) with ESMTPS id Cszkpj3P8v-h8nasg73;
Tue, 11 Apr 2017 11:43:08 +0300
(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))
(Client certificate not present)
X-Yandex-Front: mxfront1j.mail .yandex.net
X-Yandex-TimeMark: 1491900188
Authentication-Results: mxfront1j.mail.yandex.net; spf=pass (mxfront1j.mail.yandex.net: domain of panel.germovvodi.ru designates 146.185.154.178 as permitted sender, rule=[a]) [email protected]; dkim=pass [email protected]
X-Yandex-Spam: 4
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
d=germovod.pw; s=mail; h=Date:Message-Id:Content-Type:MIME-Version:Reply-To:
From:Subject:To; bh=FSXgxIC/5lXGmGIwUojsP7LKR2tlf3HDKuqZl6wdDXE=; b=gMRxO6fcM
emXKWK465LDc+ylou2MGW4e4hXTJVfNoPOMEOVhBcdfzudXvaz1WKnVvV6wKPLfA1hyfrnN7Bkmq8
Wfctij542PIqu0jrvravo2OjEM9F9kCAtPDrMXRnbcE49t1hSlT7WR8fEaezrDsdBCh4b
=a
Received: from admin by panel.germovvodi.ru with local (Exim 4.86_2)
(envelope-from )
id 1cxrOG-0001Cq-1c
for [email protected]; Tue, 11 Apr 2017 +0000 8:43:08 the
To: [email protected] the
Subject: = the UTF-8 + 0LTQvtCyINC90LAg0LPQtdGA0LzQtdGC0LjQt9Cw0YbQuNGOINGC0YDRg9CxINGD0LbQtSDRgdC10LPQvtC00L3RjyE LTcwJSDRgNCw0YHRhdC Bed and = =???? The
X-the PHP-Originating-Script: 1000: next.php the
From: = UTF-8 0JrQvtC80L Bed and / QsNC90LjRjyDCq9CT0LXRgNC80L7QstCy0L7QtNGLwrs = =????
Reply-the To: = UTF-8 0JrQvtC80L Bed and / QsNC90LjRjyDCq9CT0LXRgNC80L7QstCy0L7QtNGLwrs = =????
the MIME-the Version: 1.0
the Content-the Type: a multipart / alternative;
boundary="-----------B332FBECD17E94A13B645B77D9434E93"
Message-Id:
Date: Tue, 11 Apr 2017 08:43:08 +0000
Return-Path: [email protected]
X-Yandex-Forward: 36518250aad098f7fe3e6d56a4655e24
--------------B332FBECD17E94A13B645B77D9434E93
Content-type: text/plain; charset=UTF-8
Content-Transfer-Encoding:base64

Answer 1

SMTP banner and PTR record do not match - one of the possible reasons.
In addition, the check gives the error "Reverse DNS is not a valid Hostname". The reason is unclear.

Answer 2

For such purposes, there is a service mail-tester.com