In Outlook 2016 via EAS multipart HTML-mails with non UTF-8 charsets are not displayed correctly, e.g. Umlauts are garbled. Plain text mails with non UTF-8 charsets and HTML-Mails with UTF-8 charset are displayed correctly though.
This problem stared to occur with version 2.3.3.
Example 1, Not OK:
####################
To: [...]
From: [...]
Subject: Test-Mail Windows-1252 Multipart
Message-ID: <5650A83B.30107@...>
Date: Sat, 21 Nov 2015 18:22:03 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101
Thunderbird/38.3.0
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="------------050601050803060608060403"
This is a multi-part message in MIME format.
--------------050601050803060608060403
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 8bit
--------------050601050803060608060403
Content-Type: text/html; charset=windows-1252
Content-Transfer-Encoding: 8bit
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=windows-1252">
</head>
<body bgcolor="#FFFFFF" text="#000000">
- ä<br>
- ö<br>
- ü<br>
</body>
</html>
--------------050601050803060608060403--
####################
Example 2 OK:
####################
To: [...]
From: [...]
Subject: Test-Mail Windows-1252 Plain
Message-ID: <5650A572.7060006@...>
Date: Sat, 21 Nov 2015 18:10:10 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101
Thunderbird/38.3.0
MIME-Version: 1.0
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 8bit
- ä
- ö
- ü
####################
Example 3 OK:
####################
To: [...]
From: [...]
Subject: Test-Mail Windows-1252 HTML
Message-ID: <5650A7B1.7020103@...>
Date: Sat, 21 Nov 2015 18:19:45 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101
Thunderbird/38.3.0
MIME-Version: 1.0
Content-Type: text/html; charset=windows-1252
Content-Transfer-Encoding: 8bit
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=windows-1252">
</head>
<body bgcolor="#FFFFFF" text="#000000">
- ä<br>
- ö<br>
- ü<br>
</body>
</html>
####################
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