A cloud-based service included in Microsoft 365, delivering scalable messaging and collaboration features with simplified management and automatic updates.
From my testing, I create a transport rule to block attachment size that is greater than 1KB. However, the recipient field is quite complex.
I used "address matches any of these words" and then input the DL email address, however, it does not work. The email went through and no bounce-back mail.
I recommend you raise your idea via Feedback Portal.
Once you done submitting, please drop the link here so I and other people can upvote for you.
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