1. LowEnd computer trying to use HiEnd software. (didn't read requirements on SW box)2. Improper install of software. (again, didn't read the Readme)3. USER. (Thinks he knows it all and, all the software and hardware makers sell crap.)#3 is usally the main reason 90%+ of the time.A bit of friendly advice. RTFM. :(

Any beginners reading this, I'd ignore this rather odd 'advice' if I were you (most experienced posters here will know well what the real problems causing CTDs are): The vast majority of CTDs (certainly in my case, over the past 10 years) occur because of bgl files that 'clash', or because of missing vital texture files (bmps). With a complex setup, with the likes of Ultimate Terrain, complex payware airports, AES etc. etc. installed, t's not surprising that problems sometimes occur.I should say that I have never, and I mean not once in dozens and dozens of occurrences over the years, not been able to fix a CTD by finding the problem bgl file and editing or removing it (sometimes it's an hour's search by trial and error, switching off scenery in the scenery.cfg file until the CTD no longer occurs, then removing bgl files from that scenery folder until the culprit is found) .I'm not saying there aren't other reasons for CTDs (as most posters here will know very well), but user arrogance wouldn't account for the majority.Martin