Email as attachment (Exchange Online Office 365)

Copper Contributor

Hi Experts,


Seeking your expert advise. 


For some reason, I'm receiving an email from specific domain as an attachment. I've done the following but the issue still persist.


1. Added the sender's IP to allow list (exchange online

2. Added domain and email address to allow list.

3. By pass ATP - Created a rule using header to bypass ATP scanning

4. Added to Outlook safe sender

5. Run message trace (attached result)




Do you know why is this happening? I would really appreciate your help.





2 Replies



According to your message trace outpu there are some transport rules that are being applied. 

Have you verified that the domain in question are excluded from those rules? 


Kind Regards
Oliwer Sjöberg


Sure its not an issue on the sender side? Is this happening with other messages from other domains? Or if the message is sent to another email system like gmail? When did this start? Did it ever work correctly?