I have never had this problem before,  or anything close to it.  I have shut the  machine off (using task manager) at least a half dozen times,  and it always hangs at 86%.

 

I've been using this same machine for at least two years,  never had a problem running FSX (although at reduced settings, of course).

 

Any ideas on how to solve this problem? 

Maybe a scenery file, or AI conflict problem. Suggest start with backing up fsx.cfg, then delete that file and restart, see if that gets you in

fsx\scenery\world\scenery are there a lot of .bgl files with the name traffic in them? what did you install recently? something must have changed. set all traffic including ground to 0% and try again

Try going to your FSX.cfg and clearing out the "situation" line

 

So it will look like Situation=

Thanks,  guys.  I've been busy with medical stuff,  haven't been able to try your suggestions yet,  but thanks.