This happened to me, and I hope it won't happen to anyone else.I Had my DEFAULT flight saved as a PMDG 737-700 with the New Zealand Livery. I Uninstalled the AIrcraft using the removal tool, then Installed SU2. When I attempted to reload the game, I got an error message about an Invalid Aircraft, naming the New Zealand Livery. I Scanned the FS9 Config file, and could not find it.Solution? Delete the Default flight. It was trying to load an aircraft that didn't exist, once the default was removed, everything was fine.So, BEFORE you uninstall, to avoid this, change the default aircraft if you are using a different livery. Changing to a default MS Plane would proably be your best bet.Just posting this, to let you know what worked for me.Paul.

So you dont need the SU1 actiali.I know you have to buy the SU1 in order to get the SU2 but actiali dont need the SU1?

SU2 is now the whole product. There's no SU1 or 1.1 anymore.

Good advice .......however, while it is fustrating, it shouldn't be too much of a headache if that happens. FS will tell you that it can't find the airplane, and after a little while, it will just load the default cessna at KSEA situation........

Anthony, actually that wasn't so. When the error popped up, and I Clicked OK, I was dumped from the game. Wish it was that easy though.Paul.