[Spooky23]

They can and do whitelist all sorts of things for special cases. Microsoft is good at what they do, but they are a pragmatic company.

My guess here is that some junk folder routing is on client side, or the user flagged junky email from the same infrastructure as junk. Or, O365 tweaked some settings to address the issues with spammers using Outlook infrastructure that bypasses spam controls.

[anonn77]

I’m not sure, I created a brand new Outlook email account a while back and the welcome email went directly to spam. That just seemed kinda dumb to me.