Do you need to put in an appointment that occurred in the past for a client? You absolutely can do this:
1. Begin scheduling the appointment as you normally would, but instead of using the date picker just key in the date and select the time the appointment happened.
2. Next, remove all the reminders and uncheck the box to send the notification (as that would be mighty confusing for the client).
3. Hit Schedule Appointment, which will put that appointment under Past Appointments.