Regarding Microsoft-hosted email -- they also frequently block ALL lists
on the basis that the email was not specifically addressed to the recipient.
I wrote a tutorial for my users about how to add my list addresses to
the safe senders list (known elsewhere as a white list).
It is found here:
https://www.clinicians-exchange.org/fix-hotmail-and-outlook-to-allow-safe-mailing-lists/
At the time I was mainly thinking its a Hotmail problem -- but it's any
email address on any domain hosted at Microsoft.
They also seem to do this for any email forwarded from another address
-- very annoying when lots of email is being auto-forwarded. Does not
seem fixable by any setting that either the email account holder or the
email company administrator can adjust.
Michael Reeder
Hygeia Counseling Services
mich...@hygeiacounseling.com
(Now auto-forwarded to an address hosted at Microsoft so I have to safe
list every blessed new sender!)
------ Original message------
*From: *Jon Baron
*Date: *Mon, Nov 29, 2021 6:57 AM
*To: *Jayson Smith;
*Cc: *mailman-users@python.org;
*Subject:*[Mailman-Users] Re: Charter occasionally bouncing mail
I have had a lot of experience with these things. Here are some
observations. I have a list of 4000+ subscribers around the world. I
have SPF and DKIM but not DMARC. (I never say much point in DMARC, and
it does not seem necessary.) Right now every single one of the 4000+
subscribers accepts the mail, most of the time. Occasionally I get
msssages (from Europe) saying that the mail has been blocked because
it is a "high probability of spam" or "looks like spam". This drives
me crazy. These spam-blocking systems are unregulated. They are like
snake oil. They should not be blocking mail without telling the
recipients, and this is what happens.
A few times, Microsoft has started blocking mail to ALL addresses with
domains of outlook, hotmail, msn, or live. Sometimes this was the
result of what you are talking about. I was told to sign up for
various things, including "sender support":
https://sendersupport.olc.protection.outlook.com/snds/
You can get data on what proportion of your mail counts as spam (if
you have enough mail, as we do). When they block mail, you can
complain:
https://support.microsoft.com/supportrequestform/8ad563e3-288e-2a61-8122-3ba03d6b8d75
(the one that works for me) or just
https://support.microsoft.com/supportrequestform/
If you complain, you will get an automatic reply saying that your
problem does not qualify for mitigation and that they are almost
always correct. Then you have to respond to that. After a few rounds
of this, you will get a response from what seems to be a human being,
who will tell you that they are taking your problem very seriously,
yada yada.
The last time this happened, they were completely blocking all make for
over a week, because my IPV4 address (the one they use) was part of a
range of addresses from which spam was being sent. Of course, I have
only one ipv4 address (from a cloud server, Linode). The problem seems
fixed for now, but I am warning new subscribers not to use
Microsoft-controlled addresses.
Of course they won't tell you HOW they decide that something is spam,
as this information would just make it easier for spammers.
(But I don't see what is so bad about spam. You just delete it; it
helps if possible spam goes to a spefific folder, but any system I've
seen makes many mistakes both ways, except spamassassin, which rarely
makes a false positive. The real problem is phishing, and there have
been no randomized control trials to see whether any system can
immunize people against that. I doubt that these spam detectors do it
effectively.)
Some references:
https://answers.microsoft.com/en-us/outlook_com/forum/all/hotmailoutlook-block-list-s3140-blocks-all-new/699f3a56-406e-4804-97e2-cbe23b9bb01c?page=2
https://lists.mailman3.org/archives/list/mailman-us...@mailman3.org/thread/CQ6R3WUVVLNOA3UFFCM42GVPKQDC5SPC/
And there are several things like this:
https://mxtoolbox.com/blacklists.aspx
But the list called UCEPROTECT3 (I think) is now, happily, widely
ignored, because it is based on spam coming from a large range of ipv6
addresses on a cloud server. Spamhause does something like this too,
but you can fix it by getting a "proper" ipv6 address that specifies
the range ("/64" at the end).
Some geneneral
On 11/29/21 00:51, Jayson Smith wrote:
Hi again,
Good point about DMARC. Does anyone know if Charter suddenly started
caring about some DMARC policies on or around this past Friday? I
have my list set to munge the From: lines of messages from senders
E.G. AOL, Yahoo, etc. that publish a DMARC rejection policy.
On a slightly different topic, I've heard from a few Outlook users
that list messages are consistently ending up in their junkmail
folders. Could this be because Microsoft doesn't like the fact that
my list is causing DMARC to fail, but not actually complaining to me
about it? I could solve this problem by having the list munge the
From: line for all messages, but sometimes that causes problems with
replying. In particular, several years ago when my lists were set up
to do that, Thunderbird users were having problems sometimes replying
to the sender of a message rather than the entire list.
Jayson
On 11/28/2021 11:45 PM, Mark Sapiro wrote:
>On 11/28/21 7:58 PM, Jayson Smith wrote:
>>Hi,
>>
>>
>>One of my Mailman lists has a single member at Charter which has
>>occasionally bounced mail over the last few days. When this
>>happens, the reason given, when I look it up on their help page,
>>indicates the message I sent goes against the security policies
>>of my domain, and I should contact my domain administrator (that
>>would be me). I have SPF and DKIM set up, and a quick check at
>>dkimvalidator.com <http://dkimvalidator.com> verifies they're both working.
I assume this is
>>one of these annoying situations where Charter is seeing what's
>>clearly a transient DNS problem and treating it like a permanent
>>failure? Also I assume there's nothing I can do about this? Is
>>the problem likely to be at Charter's end or at my domain's
>>nameservers' end?
>
>
>Only guessing, but this sounds like DMARC. Does your list apply
>DMARC mitigations?
>
>If it is DMARC, the issue is the message sent to the charter
>subscriber is From:pos...@posters.domain.posters.do <http://posters.do>main
publishes
>a DMARC policy of (probably) reject. Yahoo.com <http://Yahoo.com> is one
such common
>domain. Your list modifies the message by content filtering,
>subject prefixing, adding msg_footer or some other transformation
>that breaks the posters.do <http://posters.do>main DKIM signature. Your SPF
and DKIM
>signatures pass, but they are not 'aligned' with posters.do
<http://posters.do>main, so
>they don't count for DMARC.
>
>See https://wiki.list.org/DEV/DMARC
>
>
------------------------------------------------------
Mailman-Users mailing list --mailman-users@python.org
To unsubscribe send an email tomailman-users-le...@python.org
https://mail.python.org/mailman3/lists/mailman-users.python.org/
Mailman FAQ: http://wiki.list.org/x/AgA3
Security Policy: http://wiki.list.org/x/QIA9
Searchable Archives: https://www.mail-archive.com/mailman-users@python.org/
https://mail.python.org/archives/list/mailman-users@python.org/
--
Jonathan Baron, Professor of Psychology, University of Pennsylvania
Home page:https://www.sas.upenn.edu/~baron
Founding Editor: Judgment and Decision Making (http://journal.sjdm.org)
------------------------------------------------------
Mailman-Users mailing list --mailman-users@python.org
To unsubscribe send an email tomailman-users-le...@python.org
https://mail.python.org/mailman3/lists/mailman-users.python.org/
Mailman FAQ:http://wiki.list.org/x/AgA3
Security Policy:http://wiki.list.org/x/QIA9
Searchable Archives: https://www.mail-archive.com/mailman-users@python.org/
https://mail.python.org/archives/list/mailman-users@python.org/
------------------------------------------------------
Mailman-Users mailing list -- mailman-users@python.org
To unsubscribe send an email to mailman-users-le...@python.org
https://mail.python.org/mailman3/lists/mailman-users.python.org/
Mailman FAQ: http://wiki.list.org/x/AgA3
Security Policy: http://wiki.list.org/x/QIA9
Searchable Archives: https://www.mail-archive.com/mailman-users@python.org/
https://mail.python.org/archives/list/mailman-users@python.org/
