Originally Posted by
gary_nj
Often ITA-generated itineraries can be purchased on Orbitz, even if they are not available on other sites.
... but just as often they show up on Orbitz initially, but when you then try to book it gives an error. I have the impression that the inventory is not always correct on ITA/Orbitz, and they only find out when they try to confirm with the airline. And it is not because just in that moment somebody bought the ticket - go back to ITA, and the flight still shows up...
SmilingBoy.