I don’t know of any tracking software that will tell you who deleted what, however what they need to know is that if a user has multiple delegates and any one of those delegates deletes a meeting invite from their inbox, it will delete off the calendar of the executive. They need to understand that delegation is meant to be used to give another person complete control of managing their calendar. Lots of people use delegation to grant rights to view their calendar not knowing the side effect I have descried if a delegate deletes a meeting invite. I have seen some users with 12 or more delegates and they can;t figure out where all their meetings are going! They need to remove delegates and right-click the calendar itself and grant permissions to view instead. Of course noone is going to admit they deleted a meeting, especially when they do not know deleting the invite will remove the meeting from the execs calendar. Also make sure the execs know not to delete the meeting invite off their blackberry mail. That will also remove it from their calendar. These are not “problems”, they are “features” of Outlook. You have to know and be careful.