Dear Paul, I recommend subscribing and reaching out to the “mailop” mailing list. You may not see replies from the big mail operators in the archives, but I suspect a lot of relevant people pay attention to this specific list. https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop Kind regards, Job On Fri, Jan 31, 2020 at 21:43 Paul Kelly - Blacknight <paul@blacknight.com> wrote:

Hi There,

If there are any Microsoft mail admins on the list can they please contact me ASAP. We’re having deliverability problems into you and all the usual tools don’t help with fixing problems, only diagnosing them after the fact.

Thanks,

Paul

Paul Kelly

CTO

Blacknight Internet Solutions Limited

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e-mail: paul@blacknight.com

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