Mail flow/transport rules and subaddresses

[GabeR01]

I'm reaching the limits of my patience trying to solve something relatively simple in concept and am turning to the community to point me in the right direction.

Here's the problem: When an email hits our Exchange server (Exchange Online) from outside the domain and the recipient's address contains a particular subaddress tag I need that email BCCd to a shared inbox.

I've tested a variety of mail flow/transport rules in an attempt to solve this, and I can get them to fire if using some other criteria (ex. if a specific word is found in the subject line), but never as I outlined above. An example of one such failed rule: https://imgur.com/yH149TV

Thoughts, tips, tricks? Any help would be much appreciated. Thanks in advance.

[#2]

Try using "The message > To or CC box contains" condition instead.

[#3]

@Vasil Michev Thanks for the reply. I tried as you suggested and it works. However, if I'm not mistaken, this method doesn't make use of the +tag (subaddressing) as a condition for triggering the rule. Is that correct?

Just for some added clarity, I'd like the rule to fire when the in-domain recipient address looks like: marketing+outreach AT domain.tld or JoeBlank+outreach AT domain.tld  ... really any time the "outreach" subaddress is used. Is that doable?

Thanks again!

[#4]

Use the "match" condition then, that allows you to use wildcards.

[#5]

Thanks again, Vasil. I appreciate your help!

On that note, your suggestions prompted me to try a different angle altogether. Instead of pursuing subaddressing, I opted to create aliases. It's more work and ultimately less flexible, but the results are encouraging.

Here's a quick rundown:
• An alias was created for each address the rule should act on using the same pattern as shown above. An example of that would be: marketing.outreach AT domain.tld (using "." or other accepted character in place of "+").
• Incoming messages would never show the alias in the To field of the message itself. However, they are captured/displayed in the message header. I adjusted the rule accordingly. Here's what that looks like: https://i.imgur.com/5rRtTLO.png

While I'm hoping one day to be able to leverage subaddressing in the same way, I think we've arrived at a viable solution to the problem.

Thanks again for your help!