Emails bouncing back to Microsoft emails

Hi Emily, thank you. It would be odd for it to suddenly not work, it has been fine for the last 7 years as recently as a few days ago - the issue is only with sending to hotmail and outlook emails (so far), they are sending fine to gmail, aol etc.

I have submitted a report to sender support.

I understand. But if you did have a legitimate SPF, DKIM or DMARC configuration issue, which I don't have visibility to, then this can be a real issue.

Requirements for these records have shifted from not required to soft requirement to hard rejection, so it can be normal that 7 years ago this wasn't an issue, but now it is. Microsoft's requirements were rolled out last year, starting with volume senders. This was the blog post announcing it back then: https://techcommunity.microsoft.com/blog/microsoftdefenderforoffice365blog/strengthening-email-ecosystem-outlook%E2%80%99s-new-requirements-for-high%E2%80%90volume-senders/4399730

Hi Emily,

Thank you for the extra info. However, I am definitely not a high volume sender, therefore I would not expect that to apply to me? Would this roll out have reached users such as myself who only send a handful of emails each week.

You are welcome, Laura.

I haven't been able to find any official information from Microsoft confirming that SPF, DKIM, and DMARC are now hard requirements for senders who don't meet the 5,000 emails per day threshold.

However, I am seeing a sudden increase in users reporting similar issues today. In fact, right after replying to your question, I helped another user who provided their domain name. I checked their DNS records and confirmed that they had no SPF, DKIM, or DMARC records configured at all.

Is it possible that Microsoft started applying stricter enforcement to all domains today, regardless of sending volume? Perhaps. But at this point, I don't have any official information or evidence to back me up on that.

That's one of the limitations of being an Independent Advisor. I don't work for Microsoft, so I don't have access to their internal information. I'm simply an experienced user who have product knowledge.

Regardless, I strongly recommend getting those records configured. Email authentication requirements are only going to become stricter over time, not more relaxed. Microsoft isn't the only company enforcing them. Google and other major email providers have similar requirements.

I believe it's only a matter of time before these become standard requirements for all senders, regardless of whether they send 50 or 5,000 emails per day.

Thanks @EmilyS726 I appreciate your response. I will look to get them configured regardless and hope that I am able to resolve this issue ASAP.