I’ve looked through all the rules in Outlook but it appears I can only apply them to messages which meet a certain condition. What I’m looking for is to create a rule when a certain condition is NOT met.

For instance, all emails which are marked as high importance but that are not coming from our escalation tool should be marked as normal importance (and I’ll assign it a category instead to indicate that the customer deemed it important).

I can set the condition “from people or public group” with ease but how do I set the condition “NOT from people or public group”?