I have a bit of a strange issue. When registering for an event, confirmation coming from firstname.lastname@example.org go to Quarantine for ONE specific user.
For example, I'm using Exchange Online, I have a few domains, but the following users are receiving emails directly into their Inbox from the above noreply@:
However noreply@ emails are going to quarantine for email@example.com
I bolded def.com as other users from the same domain, and different domains within the same Exchange Online account, are getting these emails directly to their inbox. This indicates to me, it is a user-issue, but within Exchange - not Outlook.
That said, I spent a few hours with Microsoft support, and whitelisted:
I think we also added an Anti-Spam Policy By-Pass (I'm not sure), but the issue persists. Finally, Microsoft had me send their engineers some reports, and in conclusion they advised me to contact Eventbrite for them to
Sender organization must update their SPF, DKIM and DMARC record so that their emails does not get mark as spam and move to quarantine.
I will try contacting Eventbrite, but personally I feel that this will not work. This is for a single email address world-wide. It is not even domain-level. I think Microsoft is just washing their hands from this.
Finally, I found this article from Eventbrite - to whitelist their IPs, but under Exchange Online I have only found Connection filters related IP whitelisting, which I assume its related to email clients.
Any help would be appreciated.