Another problem I have had with My Itineraries is that if I have an invol reroute or something happens mid-trip, they will create a new itinerary and while the old one will still appear, the option to print a receipt won't. I recently flew DCA-ORD-IND and had four reservations under My Itineraries for the same legs, three of them with flights I was trying to get on standby, and one with the real one flown.