WP Mail / Outlook / MIME multipart issues

  • My office processes many WordPress-based forms (Formidable Pro plugin) that send email receipts. Starting in the last 4 or 5 months, occasionally an email receipt will come through corrupted– equal signs and broken HTML will appear in the body of the email. It looks like the email line endings (= equal signs) end up in the middle of an HTML tag and break the code.

    I notice this only happens to messages received by Outlook/Exchange clients (in this case everyone in the office is using Outlook). The same emails CC’d to Gmail or another service do not experience the corruption.

    When viewing the source code of the email in Outlook the following error is present: “This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible.”

    The situation is made more confusing and difficult to address by the following details:
    – This doesn’t appear to be a problem specific to Formidable Pro. Other plugins that send email via WordPress are also affected.
    – The problem arose in the past few months
    – Not every email is affected, Person A’s form submission email may come through fine, Person B’s form submission email is corrupted (coming from the same form)– with seemingly no pattern
    – Mail coming from other non-WordPress applications (such as a ticketing system, a custom PHP form, etc.), on the same web server, using the same SMPT for outgoing mail do not have this problem

    The only conclusions I can make are that it is some combination of WP Mail, MIME, and Outlook

    Any help on what direction I can take in further diagnosing this issue would be greatly appreciated

    Thank you

Viewing 3 replies - 1 through 3 (of 3 total)
  • Thread Starter sjlevy

    (@sjlevy)

    Here is a screenshot and redacted header:
    https://i.stack.imgur.com/YmzMW.png

    Received: from smtp.school.edu (XXX.XXX.XXX.XXX) by email.school.edu
 (XXX.XXX.XXX.XXX) with Microsoft SMTP Server id 14.3.266.1; Sun, 15 Nov 2015
 21:15:40 -0600
DKIM-Signature: [v=1; a=rsa-sha1; c=relaxed/relaxed;
  s=s1024; d=school.edu;
  h=subject:to:date:from:message-id:mime-version:content-type;
  bh=XXXXXX;
  b=XXXXXX
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
  s=s1024; d=school.edu;
  h=subject:to:date:from:message-id:mime-version:content-type;
  b=XXXXXX
Received: from WWW1.school.edu ([XXX.XXX.XXX.XXX]) by smtp.school.edu with
 Microsoft SMTPSVC(7.0.6002.18264);  Sun, 15 Nov 2015 21:15:40 -0600
Subject: =?UTF-8?B?TGlicmFyeSAtIFXXXXXgU3VnZ2VzdGlvXXXXXXtaXR0ZWQgb24gTFNVIExXXXXXcm1z?=
To: <[email protected]>
X-PHP-Originating-Script: 0:class-phpmailer.php
Date: Mon, 16 Nov 2015 03:15:40 +0000
From: School Web <[email protected]>
Message-ID: <[email protected]>
X-Priority: 3
X-Mailer: PHPMailer 5.2.10 (https://github.com/PHPMailer/PHPMailer/)
Reply-To: <[email protected]>
MIME-Version: 1.0
Return-Path: [email protected]
X-OriginalArrivalTime: 16 Nov 2015 03:15:40.0590 (UTC) FILETIME=[126F9CE0:01D1201D]
X-MS-Exchange-Organization-AuthSource: email.school.edu
X-MS-Exchange-Organization-AuthAs: Anonymous
X-MS-Exchange-Organization-PRD: school.edu
X-MS-Exchange-Organization-SenderIdResult: Pass
Received-SPF: Pass (email.school.edu: domain of [email protected]
 designates XXX.XXX.XXX.XXX as permitted sender) receiver=email.school.edu;
 client-ip=XXX.XXX.XXX.XXX; helo=smtp.school.edu;
Content-type: multipart/alternative;
    boundary="B_3530511021_187771850"

> This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.

--B_3530511021_187771850
Content-type: text/plain;
    charset="UTF-8"
Content-transfer-encoding: 7bit

Affiliation:<=strong> XXXXXX Student
Comments: 1. I would feel a lot safer if, after a certain tim=, we would have to swipe our IDs to have access into the building.
<=r/>2. I wish the undergrads did not have access to our classrooms or our l=brary, especially during finals season. 

3. I would appreciate i= if the library would allow us to have the study rooms for more than 3 hou=s IF all of the other study rooms are not full. I don't see the rationale =ehind kicking us out when there is no one else waiting for the room and th=re are 6  other empty ones not being used... 

--B_3530511021_187771850
Content-type: text/html;
    charset="UTF-8"
Content-transfer-encoding: quoted-printable

<html>
<head>
<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dutf-8">
</head>
<body>
<table cellspacing=3D"0" style=3D"font-size:12px;line-height:135%; border-b=3Dtto=
m:1px solid #dddddd;">
<tbody>
<tr style=3D"background-color:#eeeeee;">
<th style=3D"text-align:left;color:=3D444444;padding:7px 9px;border-top:1px sol=
id #dddddd">
<strong>Affiliation:<=3Dstrong></strong></th>
<td style=3D"text-align:left;color:#444444;padding:7px 9px;bor=3Der-top:1px sol=
id #dddddd">
XXXXXX Student</td>
</tr>
<tr style=3D"background-color:#ffffff;">
<th style=3D"text-align:left;color:=3D444444;padding:7px 9px;border-top:1px sol=
id #dddddd">
<strong>Comments:</st=3Dong></strong></th>
<td style=3D"text-align:left;color:#444444;padding:7px 9px;border=3Dtop:1px sol=
id #dddddd">
1. I would feel a lot safer if, after a certain tim=3D, we would have to swip=
e our IDs to have access into the building.
<br>
<=3Dr/>2. I wish the undergrads did not have access to our classrooms o=
r our l=3Dbrary, especially during finals season.
<br>
<br>
3. I would appreciate i=3D if the library would allow us to have the study ro=
oms for more than 3 hou=3Ds IF all of the other study rooms are not full. I do=
n't see the rationale =3Dehind kicking us out when there is no one else waitin=
g for the room and th=3Dre are 6
 other empty ones not being used...</td>
</tr>
</tbody>
</table>
</body>
</html>

--B_3530511021_187771850--
    Jason Hendriks

    (@jasonhendriks)

    What’s WP Mail? This message looks corrupt to me.

    Lisa

    (@lisafoxnet)

    Hi-

    Have you tried disabling the html function and seeing if the error is still occuring?

Viewing 3 replies - 1 through 3 (of 3 total)
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