Intermittent Missing Emails From One Specific Sender on Hotmail Account

Question

I am having an issue with my Outlook.com / Hotmail account where emails from one legitimate sender sometimes do not arrive.

They are not appearing in Inbox, Junk, Deleted, or Archive, and I have confirmed the sender is not blocked. I have also checked rules and added the address to Safe Senders.

Some previous emails from this same address have arrived normally, but others seem to disappear completely.

Has anyone experienced this with Outlook.com, or does anyone know what might cause intermittent delivery problems from a specific sender?

Answer 1

Hello

Who's the sender's domain address, for example, @business.com?

These days, a single email address or domain is often used by several different sending services, which is very common for businesses. I am IT for my organization, and we have multiple services authorized to send on our behalf. For example, Salesforce sends sales follow-up emails, Constant Contact sends newsletters, Square sends invoices and receipts, and Microsoft handles our main email service. When a business allows third-party services to send email using its domain, all of those services must be included in the SPF record in THEIR DNS. For example, if I include Salesforce and Constant Contact in SPF but forget to include Square, then any receipt sent from Square could be rejected because SPF would fail. From the recipient’s side, there is no obvious difference because every message still appears to come from @business.com. That is why people often describe it as “some emails arrive, some don’t,” when in reality the messages are being sent from different services and one of them is not properly authorized.

So, I suspect that's the case, which is usually the most common culprit. And if that's indeed the case, only they can fix it, not you or Microsoft.