How to undo Schedule Action Quickstep

If, while reading a message, I use "Schedule action" Quickstep, the message is put into an appointment. If I change my mind and close the appointment before saving it, both the draft appointment and the original message are gone. What happens to the original message when I use the "Schedule Action" Quickstep to put the message into an appointment? I need to recover either that original message or the copy of it that was in the unsaved appointment.