[Mailman-Users] Outlook blocking all email - "email harvesting"

[Jim Dory]

I've got a plan with Hawkhost on a VPS server for our community, subscriber
only, trade and announcements email list.

Outlook has completely blocked us so I've recently gotten messages from
mailman bounces that about 400 of our subscribers (all the hotmail, live,
outlook, etc. users) have been disabled.

I have signed up with the SNDS program and it reports that email is blocked
because we are "email harvesting". (I am working with Hawkhost on a trouble
ticket). I've tried to sign up with the JMRP program as well but when I
click the link I get sent back to the SNDS page and cannot figure out how
to get out of that loop to get actual user feedback complaint reports, if
any. But that is a different issue.

I am hoping you folks can shed some light on what to look for.

Here is the report after sending info to
https://support.live.com/eform.aspx?productKey=edfsmsbl3&ct=eformts&wa=wsignin1.0
:

Dear James Dory

We have completed reviewing the IP(s) you submitted. The following table
contains the results of our investigation.

More information needed
198.252.110.38
There are indications that the above IP(s) are engaged in namespace mining.
Outlook.com is blocking all email sent from this IP.

Namespace mining is a method commonly used by malicious senders to generate
lists of email addresses. This approach uses automation to sift through
possible email names seeking to identify valid email addresses, e.g.,
Joe at domain.com, John at domain.com, and Josy at domain.com.

You must correct the problem and you must stop the behavior described
above. We recommend that you work with your email or network administrator
to review the logs of your email servers. Check the sending log files and
concentrate on logs that are sending to nonexistent @hotmail.com, @live.com,
@msn.com, @outlook.com?with <http://outlook.com/?with> multiple tries and
failures.