Re: mails get flagged in OutLook
Una Smith <[email protected]> Mon, 9 Feb 2026 16:57:14 +0000 (UTC)
| Newsgroups | gmane.mail.mutt.user |
|---|---|
| Message-ID | <[email protected]> |
------=_Part_559608_1747557677.1770656234272
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Matthias,
Your advisory "Mails in HTML will not be read! Please, only plain text." ne=
eds to be in the body of your emails, perhaps in your signature, not in you=
r headers. =C2=A0Very few recipients ever read their headers; =C2=A0many do=
n't even know headers exist.
Una
On Monday, February 9, 2026 at 09:53:53 AM MST, Matthias Apitz <guru@un=
ixarea.de> wrote: =20
=20
=20
Hello,
I'm adding to all my mails sent with mutt (like this one) two X-header
lines:
=C2=A0 =C2=A0 X-Operating-System: FreeBSD 14.0-CURRENT r1400094 (amd64)
=C2=A0 =C2=A0 X-message-flag: Mails in HTML will not be read! Please, only =
plain text.
I got informed by an reader of a mailing-list that my mails get flagged
in his OutLook mailbox with a small red flag. Technically this is added
by a Microsoft SPAM protection which adds into my mail a header among other
stuff a line like this:
```
=C2=A0 =C2=A0 X-Microsoft-Antispam-Mailbox-Delivery:
=C2=A0=C2=A0=C2=A0 ucf:0;jmr:0;auth:0;dest:I;ENG:(910005)(944506478)(944626=
604)(4710137)(4713098)(499
9163)(920097)(930201)(20251009147)(140003);
```
I did tests with an OutLook destination I've access to and the "culprit"
seems to be only this X-header:
=C2=A0 =C2=A0 X-message-flag: Mails in HTML will not be read! Please, only =
plain text.
Any comments on what could he do or what could I do?
Thanks
=C2=A0=C2=A0=C2=A0 matthias
--=20
Matthias Apitz, =E2=9C=89 [email protected], http://www.unixarea.de/ +49-176=
-38902045
Public GnuPG key: http://www.unixarea.de/key.pub
Jens Spahn (CDU, 11.3.2025 in FAZ):
"Wir k=C3=B6nnen uns verteidigen lernen oder alle Russisch lernen."
"We can learn to defend ourselves or we can all learn Russian."
"O podemos aprender a defendernos o todos podemos aprender ruso."
Ich ziehe vor, Russisch zu lernen. I prefer to learn Russian.
Yo prefiero aprender ruso.
=20
------=_Part_559608_1747557677.1770656234272
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
<html><head></head><body><div class=3D"ydpdde30395yahoo-style-wrap" style=
=3D"font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px=
;"><div></div>
<div dir=3D"ltr" data-setdir=3D"false"><div dir=3D"ltr" data-setdir=
=3D"false" style=3D"outline-color: currentcolor !important;">Matthias,</div=
><div dir=3D"ltr" data-setdir=3D"false" style=3D"outline-color: currentcolo=
r !important;"><br></div><div dir=3D"ltr" data-setdir=3D"false" style=3D"ou=
tline-color: currentcolor !important;">Your advisory "Mails in HTML will no=
t be read! Please, only plain text." needs to be in the body of your emails=
, perhaps in your signature, not in your headers. Very few recipients=
ever read their headers; many don't even know headers exist.</div><d=
iv dir=3D"ltr" data-setdir=3D"false" style=3D"outline-color: currentcolor !=
important;"><br></div><div dir=3D"ltr" data-setdir=3D"false" style=3D"outli=
ne-color: currentcolor !important;">Una</div><div><br></div></div><div><br>=
</div>
=20
</div><div id=3D"ydp798526aeyahoo_quoted_1331481206" class=3D"ydp79=
8526aeyahoo_quoted">
<div style=3D"font-family:'Helvetica Neue', Helvetica, Arial, s=
ans-serif;font-size:13px;color:#26282a;">
=20
<div>
On Monday, February 9, 2026 at 09:53:53 AM MST, Mat=
thias Apitz <[email protected]> wrote:
</div>
<div><br></div>
<div><br></div>
=20
=20
<div><br>Hello,<br><br>I'm adding to all my mails sent with=
mutt (like this one) two X-header<br>lines:<br><br> X-Operati=
ng-System: FreeBSD 14.0-CURRENT r1400094 (amd64)<br> X-message=
-flag: Mails in HTML will not be read! Please, only plain text.<br><br>I go=
t informed by an reader of a mailing-list that my mails get flagged<br>in h=
is OutLook mailbox with a small red flag. Technically this is added<br>by a=
Microsoft SPAM protection which adds into my mail a header among other<br>=
stuff a line like this:<br><br>```<br> X-Microsoft-Antispam-Ma=
ilbox-Delivery:<br> ucf:0;jmr:0;auth:0;dest:I;ENG:(910005=
)(944506478)(944626604)(4710137)(4713098)(499<br>9163)(920097)(930201)(2025=
1009147)(140003);<br>```<br><br>I did tests with an OutLook destination I'v=
e access to and the "culprit"<br>seems to be only this X-header:<br><br>&nb=
sp; X-message-flag: Mails in HTML will not be read! Please, only pla=
in text.<br><br>Any comments on what could he do or what could I do?<br><br=
>Thanks<br><br> matthias<br><br>-- <br>Matthias Apitz, =
=E2=9C=89 [email protected], <a href=3D"http://www.unixarea.de/" rel=3D"nofo=
llow" target=3D"_blank">http://www.unixarea.de/</a> +49-176-38902045<br>Pub=
lic GnuPG key: <a href=3D"http://www.unixarea.de/key.pub" rel=3D"nofollow" =
target=3D"_blank">http://www.unixarea.de/key.pub</a><br><br>Jens Spahn (CDU=
, 11.3.2025 in FAZ):<br>"Wir k=C3=B6nnen uns verteidigen lernen oder alle R=
ussisch lernen."<br>"We can learn to defend ourselves or we can all learn R=
ussian."<br>"O podemos aprender a defendernos o todos podemos aprender ruso=
."<br><br>Ich ziehe vor, Russisch zu lernen. I prefer to learn Russian.<br>=
Yo prefiero aprender ruso.<br></div>
</div>
</div></body></html>
------=_Part_559608_1747557677.1770656234272--