How to adjust (not set) SCL for incoming messages in Exchange Online

[Jay Carper]

Setting a specific SCL for an incoming message is easy, but I can't find a way to reduce or increase an SCL based on specific criteria. Is this possible with Exchange Online? If so, how do you do it?

This is a trivial task in every anti-spam product I've ever used except for Exchange/EOP/Defender. 

(Irrelevant, but relevant to a decade-long trend in Microsoft UIs: The Tech Community site has become the most unintuitive, obscure tech forum I have ever seen. The most basic functions are hidden or absent.)

[#2]

The only thing that comes close to this is toggling the criteria under "Spam threshold and properties" section, for example "Numeric IP address in URL".

[#3]

Working with Microsoft products is so frustrating! They offer a billion complicated features that nobody wants but not something simple like this that everyone wants.

[#4]

Also unrelated to this question, but relevant to the techcommunity interface. How do I get rid of the survey popup? I've clicked the No Thanks button, filled out the survey, ignored it...it still pops back up every few minutes.

[#5 · Accepted solution]

After going back and forth with Microsoft for over a week, I finally got a definitive answer on this question:

"I have finally received a response in regard to your inquiry. It was checked and double checked again to provide you the most accurate answer. No, there is unfortunately no way to subtract 1 from a message's spam score based on the sending domain even with Microsoft 365 Defender. We can only whitelist or set the SCL specifically as you already know. "

[#6]

Hi Jay,
theoretically you can create a Power Automate flow that will do what you want.