Duplicate of Bug#14490

My problem is a "serialization failed"

In Dynamic View, I get this error message for the following letter header:

"Delivered-To: my@same.com
Received: from wsip-174-79-150-104.cl.ri.cox.net ([174.79.150.104]
helo=brightemailmarketing.com)
         by my.server.com with smtp (Exim 4.63)
         (envelope-from <CongressMed@brightemailmarketing.com>)
         id 1gJinW-0003Da-Tc
         for my@same.com; Mon, 05 Nov 2018 18:36:23 +0100
Received: from GHS70886 ([192.168.86.40]) by brightemailmarketing.com
with Microsoft SMTPSVC(6.0.3790.4675);
         Mon, 5 Nov 2018 12:36:21 -0500
From: "COGI Congress" <CongressMed@brightemailmarketing.com>
To: emy@same.com
Reply-To: CogiReply@brightemailmarketing.com
Subject: Last Chance to Save .100 on Fees - Controversies in OB/GYN
and Infertility
Date: Mon, 05 Nov 2018 12:36:21 -0500
Message-ID: <20181105-12362135-fe4@GHS70886>
MIME-Version: 1.0
Content-Type: text/html
?..
"
a possible header problem in HEX the 0x80 before 0x31:
?Subject: Last Chance to Save .100 ...?
53 75 62 6A 65 63 74 3A 20 4C 61 73 74 20 43 68 61 6E 63 65 20 74 6F
20 53 61 76 65 20 80 31 30 30

serialization error... unable to load inbox!

After that, inbox will not load. This is independent of session and cache.
basic view all working.

Users love the dynamic view, it is difficult for them to tell the problem.
From a similar letter, the horde becomes unusable in a dynamic view.
I can send the problem mail to maildir format.

How to do this.
This is the BUG?