@thunderbird

I observe some weird behaviour from my organisations #outlook server. I use #thunderbird as a desktop client. When I send a message to an unknown recipent, the non delivery report gets flagged as junk from outlook and will never be delivered into the inbox. All support staff I am asking are trying to convice me, I am doing something wrong or that is just the way it is.

E.g. #microsoft says: "This is not a misconfiguration in the traditional sense (such as no broken SPF/DKIM/DMARC, no transport rules required). Rather, it relates to how EOP handles NDRs based on the originating client’s submission method. It aligns with Microsoft’s design: Outlook web/desktop clients receive preferential treatment for internal mail flow."

Anyone else observed similar problems?