Exchange Online Rules (Reject but allow message to be delivered)


We're getting email with a lot of vulgarity and I been ask to:

-Allow the message to proceed to recipient but modified Subject indicating this message contains vulgarity

-Send an NDR/Rejected message to the sender with info on why it was rejected

I was able to create a rule to modified the Subject and I created a second rule that will send an NDR with a custom message. The issue I'm having, when I send the message with vulgarity body or subject, the message doesn't get sent to the recipient with a modified header but gets rejected and NDR is send to sender.

How can I setup an Exchange Online rule that will allow the message to be delivered to recipient with a Modified Header, at the same time send a NDR/Reject to the sender indicating the email contain vulgarity.

Thank You,


2 Replies

You can't, since you have selected to reject the message any subsequent actions such as changing the subject will be ignored.


I was able to set up an Exchange Online Rule that will allow the message flow to recipient with an appended Subject [*Vulgarity*]. Within the same rule I added a BCC to a mailbox. The Mailbox was created with auto-reply can response, allowing the user to receive the email and send a reply to the sender.


It all worked great excepts my list of Bad Words. The list contain words commonly used like "balls" creating a lot of false positive, will need to fine tune the list.