Last year we released the Reply-all Storm Protection feature to help protect your organization from unwanted reply-all storms. This feature uses global settings applicable to all Microsoft 365 custom...
Updated Mar 31, 2023
Version 6.0
Blog Post
KevinShaughnessy
Microsoft
MicrosoftMisterD3k Thanks for the feedback! Glad you like the feature - we hope it helps! 🙂
We will definitely be evaluating the possibility for lowering the minimum number of recipients at some point in the future - first we need to evaluate the actual performance and cost impact of logging so much data from all the threads in the service with 1000+ recipients (we have to log all such threads before we can evaluate whether it's a reply-all storm or not). We won't lower the number of replies though - at least not given how we currently detect reply all storms. The feature currently doesn't do any content analysis or pattern matching, so it's based solely on number of replies, recipient count, over an hour. So folks would likely end up with more false positives blocking *valid* threads if they set it below 5. Even at 5 organizations will likely hit more false positives than they'd prefer, and will probably find themselves raising it closer to the default of 10.
Hope that makes sense!
Best wishes,
Kevin Shaughnessy
Sr. Program Manager
Exchange Online Transport