Will there be any conflicts if FSX: Box and FSX: Steam Editions are installed on the same computer?
Great question.
If you already have FSX Gold Edition and add-ons installed they will only be accessible through your existing installation. They will not be duplicated across the original edition and Steam Edition of the simulator.
If you wish to access your add-ons via FSX: Steam Edition you will need to reinstall your add-ons, pointing them toward the Steam Edition of the simulator.
We have worked to make sure the two versions of FSX can coexist, but we cannot guarantee that in all circumstances there will be no problems. If you have a very extensive add-on collection, you might want to consider installing FSX and FSX Steam Edition on separate PCs.