After installing some scenery upgrades (MegaSceneryX for SoCal and Las Vegas) I opened FSX and during the opening of FSX, a window opened indicating progress in the installation of the scenery files and then the progress bar indicated completion of the scenery installation.I should then see a screen for open a flight and get some sound. Unfortunately what I got a a screen that said "Fatal Error" and FSX is restarting. FSX then restarted, the circle thingy goes around & around but no select a flight screen opens, a window opens saying, "A problem caused the program to stop working correctly . Windows will close the program and notify you if a solution is available." Well that never occurs, and I close that window and I'm back to my clean desktop. I tried rebooting and got the same error message sequence. I inserted by FSX disk and did a repair, and the problem with FSX on opening is still there ---- can't open FSX. Any suggestions; should I uninstall the MegaSceneryX files, should I to back to an earlier system restore point, or should I do something different?I'm running FSX (when it ran) on VISTA Ultimate, with SP1, in DX10 Preview mode. I also have ActiveSky/X Graphics, MyTraffic, EZGPSv4, FSDiscover loaded with FSX along with several addon planes and addon scenery files in addition to MegaSceneryX SoCal & Las Vegas. I donno, do I have too many addon files for my computer to handle FSX? I've got 4-Gig of RAM.

It could be a couple of things. First it may be a corrupted logbook, locate the logbook.bin file in your MY DocmentsFlight Simulator X Files folder and rename it (Common practice is to just delete it, but I never delete anything unless I really have to, just in case). If that's the problem, FS will restart and a new logbook will be created. If that don't work, sometimes the fsx.cfg file itself gets corrupted, you can rename that and again let the system build it new. You will need to manually add any tweaks, you have done to it prior. Or it may be your scenery installation, in which case you should uninstall it. I would try at least the logbook solution first, as that is a common cause for FSX not loading!

Tom, I tried those suggestions, same result. I renamed, then moved the logbook.bin file to another Temp Folder, away from the Flight Simulator Files folder. I don't have a fsx.cfg file; I gave three cfg files separate names - fsx1.cfg, fsx2.cfg and fsx3.cfg all have slightly different settings. I moved all three to that temp folder. I uninstalled the MegaSceneryX files. FSX said it was building my scenery files, then after completing that step, it reverted back to my original problem, "fatal error". I'm puzzled, I'd hate to uninstall FSX and start all over again, I've got so much stuff on FSX now, it would take me a day or more to go back to RTM and load all those files/programs again.