Have you used this form? I feel your pain.
https://support.microsoft.com/en-us/supportrequestform/8ad563e3-288e-2a61-8122-3ba03d6b8d75
From: NANOG <nanog-bounces+tony=wicks.co.nz@nanog.org> On Behalf Of Brock Tice
Sent: Tuesday, 21 July 2020 4:11 am
To: nanog@nanog.org
Subject: Issues with deliverability to hotmail -- any Microsoft contacts?
We have been having issues delivering email to hotmail users again, no bulk mail, just various personal emails from a server on our network. We have signed up for SNDS, only identified one mail server of a customer on our network that was flagged as an issue, and it has been remedied, no longer showing in SNDS.
We have repeatedly requested removal of our subnet from their block list and it has not worked. MS has done a great job of making it impossible to contact anyone about this. Does anyone have pointers on what else can be done or whom we should contact to get this resolved?
Thanks,
--Brock
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