Outlook allows double booking a resource (meeting room) even though the Resource Policy is showing UNCHECK of this option "Allow conflicting meeting requests".
We've tried to check and uncheck, but still not working. I believe it used to work initially, not sure why it stopped working all of a suddent allowing people to double book the room.
BTW, it's Exchange 2010, not 2013 but it's not in the list of selection.