You will need to make sure that you have either SP2 or Acceleration for FSX. They are a part of the Minimum System Requirements to be able to use Weapon for FSX properly.

- Microsoft® Flight Simulator X SP2 or Flight Simulator X Acceleration.

There are links for SP1 for FSX (different languages) here: http://www.microsoft.com/Products/Games/FSInsider/downloads/Pages/FlightSimulatorXServicePack1.aspx

And there are links SP2 for FSX (different languages) here: http://www.microsoft.com/Products/Games/FSInsider/downloads/Pages/FlightSimulatorXServicePack2.aspx

You must install SP1 before installing SP2, so download and install them both just to be on the safe side. If you still have problems, we'll try something else.

Mark