Well it came back again, the dreaded CTD, just when I thought it was solved.So, let me stage how this developed, and maybe someone will hit on the solution. -Clean, default install. I ran the sim like this for a few days with no problems.-Replaced some default AI with FSP, Aardvark, and PAI models. Used a Tomkiewicz Learjet and Gulfstream in place default Learjet. I didn't add to the TTool generated aircraft list, just substituted. No problems.-Using KPHX only as experimental airport, I added KPHX (Richard Mohammed)AFCAD2 with AFCAD 2.21. I added AI flights with TTools 2.02. Everything still OK-Added Wings of Power WW2 bombers set. This comes with an installer that also adds a seperate aircraft list and flightplans list that TTools sees and can be selected to decompile. I subsequently deleted these files as unecessary, and a possible reason for the CDT. -I slowly added AI aircraft from Aardvark, FSP, PAI, CDAI, and the Tomkiewicz-Waldron collection. I kept a log of each aircraft and texture added. I concluded KPHX and AI was sound. -I moved to KLAS and added a KLAS AFCAD2 file. Everything still OK.-More TTools flight plans added to KLAS. This KLAS AFCAD2 file had proved stable in the past.-Attempted first long flight with the Arado twin jet WW2 bomber from Wings of Power. Left KLAS bound for KPHX. CTD occurred approx 30 miles south of KLAS and happened as I switched views from cockpit to external view. -Now the strange part. The CTDs occur earlier and earlier. For example. The first hint of trouble comes when exiting the sim when a return to desktop after exiting causes the "Microsoft Flight........has encountered a problem" box to appear.Subsequent to that event, the CTD occurs as I described above, after take-off about 10 minutes into flight. In next attempt to use FS9, the CTD occurrs just a few seconds after the sim places your aircraft at the starting point selected whne you begin a flight. After this CTD, and all that follow, the "Microsoft Flight......hasencountered a problem" box doesn't show-up. We just go back to desktop. Next attempt to use FS9 will cause a CTD when aircraft selection occurs. Next attempt to use FS9 will cause a CTD as the game starts loading.For awhile, it seemed the CTD occurred when I either used, or added to the game aircraft folder, the Howard 500 flyable. But when I deleted it, the CTD happened anyway.And I haven't added anything after the first CTD event. It's like a cascade effect that happens earlier and earlier.I've also noticed the mouse arrow will appear on screen at times, even when I haven't touched the mouse or jarred it.So I'm wondering aloud here;-Is a possible conflict with internal software accessing the sim conflicting with its operation, hence the appearence of the mouse cursor.-Do I have enough RAM? 512 DDR. I know it's not optimal, but could the lack of it cause something to react and cause a CTD?????Well that's the latest. Any help would be appreciated 'cause I'm lost, exasperated, and frustrated. Thanks a bunch everyone, for just reading my post.Rick (KMKE)

It appears to be your video card drivers are causing the problem with the little info you have provided. You didn't indicate what was stated in the error messages you received. Sometimes they'll say MSFS has encountered a problem at module sim1.dll or terrain.dll or G2D.dll, etc. If you didn't get this info you still can if you are using Windows XP. The error msg is a valuable clue. Goto Administrative Tools>Computer Management>System Tools>EventViewer then click on Application and/or System and view the error messages for the dates FS9 crashed on your system. Sometimes MS offers a possible solution to your problem by clicking on the link they provide in the message. You have plenty of system RAM especially for the KLAS area. There are way too many causes for FS9 crashes. Bad AFCAD's, duplicate AFCAD's, Scenery.cfg corrupted, aircraft not properly installed, missing gauges, problems with the panel.cfg or aircraft.cfg, corrupted .dll's within the Modules folder, just to name a few which are internal to FS9. Of course there are a myriad of possibilities with your computer and/or operating system. Anytime you receive a CTD I would recommend you first uninstall/reinstall your video card drivers and, if that fails to fix the problem, start looking at all the other possible solutions. Uninstalling addons one by one until the CTD's stop might fix your problem too but that can be time-consuming as uninstalling/reinstalling FS9. I remember having unexplained CTD's in the past and I fixed the problem by NOT uninstalling my video card drivers (ATI) but reinstalling the drivers manually (i.e., going to your Device Manager, Clicking on Display Adaptors, clicking on update driver and then telling the system where your video card drivers are located and clicking on the appropriate INF file). Downloaded ATI drivers are unzipped to an ATI directory before install so this is fairly easy to do. Not only did my CTD's stop but my FPS increased substantially too. Thanks for listening. Hope you get your CTD problem fixed.Ciao,Jim

Thanks Jim.Video card drivers are NVidia 61.77. GeForce FX 5700, 256 DDR RAM, 4/8X AGP.Intel mobo, P4A Northwood at 2G.Now that I think of it, I'm not sure my mobo supports 4X AGP. I'll have to check on this. But I appreciate the response.I've uninstalled FS9, including all config. docs and the Wings ofPower aircraft, and all added AI aircraft.I am installing FS9 again and will proceed with caution as I use add-ons. I'll post as I progress through this.Man, this has got me baffled!! Maybe I should try FS2K2 again. That gave me no trouble. If I have trouble with it, then the probelm is greater than just FS9.Rick