But this program called SimAccess from FlightSim Estonia, fixed my (hopefully) last Prepar3d V2 problem.
I found that every time I tried to save changes, the program would crash. No warning. Just crash.
Figuring that it might be permissions related, I reinstalled Prepar3d V2 to my secondary drive, free of any limiting permissions. Same problem. Crash, no warning.
I then spent a day trying to track down every Prepar3d file and folder to change its permissions & access rights. It still crashed, but now it gave me a popup saying it had crashed, before it disappeared.
The biggest problem this created for me was in assigning buttons and levers in Prepar3d. To say the least, that made it a little hard to fly.

The LM Prepar3d team seems to have a problem with error handling & reporting.
It's as simple as simple can be, download & run SimAccess. You run it once, and you're done.

It did a superb job of tracking down my Prepar3d folders & files. All I had to do was click on OK.
I can't say if this'll help everyone, but it did solve my latest Prepar3d problem, so give it a try.
It'll create a System restore point for Windows 7 & 8 if you think that you may need to revert the changes.