Installing problems with safe disk and just flight programs

Hi,

     I just reseaved a JustFlight game called Airbus series volume1. I got the game for windows vista, Flight Simulator X. The game was made by Wilco Publishing, JustFlight and feelthere. When i try to install the game the computer tells me "please insert the correct disk" when the disk is in the drive. In the little book that comes with the game under the common questions they have somthing about it but all the ways that they have to fix it dont work for me. They all say somthing about "safe disk" being the problem but i dont know how to work around this or fix it. I hope some one here can help me out with this. 
                                                                                        from,
                                                                                             Luke Galmarini