I am experiencing CTDs randomly to the point where I lose about every other flight. Today, I tried flying from Burbank to Seattle twice and both times I had a CTD (not a blue screen). I am only operating FS9.1, Radar Contact 4.2, AISeparation, and ActiveSky6. I also run FSNav within FS9. Prior to flying, I shut off my screen saver and Webroot Spy Sweeper applications.When I get a CTD only FS9 goes away. I get a desktop view but the other applications are still running. My first CTD was at the 1 hour point in the two hour flight. The second was when I was decending to 11,000 ft about 60 miles from Seattle. Needless to say, having a CTD after that long is very frustrating :-mad Between flights, I searched the forums for advice and did the following: I ran ScanAFD to look for duplicate AFCADs. Only 2 duplicates and those were KBUR and KCLE both from Shez's sceneries and should not be problems. I also ran Flight Sim Manager and did find several scenery errors which I corrected with the program. I had just ran a register clean and disk defragmentation yesterday so no problems there. Now, the curious part. I looked at Event Viewer and for both CTDs I get the following errors (3 of them): The description for Event ID (0) in Source ( ) can not be found. The local computer may not have the necessary registry information or message DLL files to display messages from a remote computer. You may be able to use the /AUXSOURCE flag to retrieve this description; see Help and Support for details: The following information is part of the event: 3. This error is followed 1 second later with a similar message ending with the number 6. And, this is followed less than 1 second later with another similar message ending in 7. I would appreciate any help or direction anyone can give. It's so frustrating to lose a flight after a long while that it's almost not worth the effort any longer. I have tried everything that I found in the forums as advice to no avail. Another thing: these CTDs have been ongoing for quite a while and occur all over the map. In California, Washington, Alaska, you name it. The error messages above almost sound like another computer is sending me something. AS6 weather? Any help would be appreciated. Thanks.

Steve; I had the same problem a while back. After much hair pulling andgnashing of teeth, turned out to a bad stick of memory. Memtest86 did not find it, neither did any other of the diagnostics. Finally pulled 1 stick of RAM and bingo. Now in all fairness, thereason Memtest86 didn't find it was because the memory would run, butnot at its rated speed.

Bad RAM makes a lot of sense. I was persuing software fixes and forgot about the hardware. I'm off to look for Memtest86. A Bad RAM chip would explain why the sim just "disappears" from the PC at different times. Thanks for the pointer. I will report back to the results.

Downloaded MemTest86 and made a bood disk. However, the test stalls at the beginning of Test #3.... Just freezes. I ran tests with Sandra Software and benchmarked my memory and it showed all was ok. Sandra also showed that I had a HP Photo program hogging a lot of my memory so I disabled it at start up.Don't know why MemTest86 freezes up. Could be bad RAM?

I purchased a new 1Gb memory stick and haven't had a CTD (crossed fingers) since. I now have 1.5Gb memory and FS is much smoother. Apparently, I had a bad stick of 500 Mb memory in the 0 slot.