When sending a Project Announcement, each member gets a message individually. So if 50 people are members of Project XYZ, then the Project Manager's Sent Items folder suddenly has 50 messages counting against his quota. Project Announcements need to be sent by the MailBot, or at least not be added to the Sent Items folder. FIXED: I still send the message from the Project Manager (so people can reply to the sender) but I treat the sent messages as if the Project Manager has deleted the messages from his inbox.