I have 5 controllers set up for each of my flight sims, so it takes some doing to get everything set up just how I want it. That's why I like having the option to save configurations. DCS World is excellent at this.
Prepar3D isn't!

I saved the assignments for my 3 'button' controllers and my G940 HOTAS to an xml file, as is recommended for P3D. But now I want to import them after the reinstall, it doesn't want to know. It goes through the motions - to the point where my joystick twitches as the assignment xml is imported - but actually, nothing changes from the default config.
So I thought I'd be clever and replace the "Standard" xml with the one I'd exported for my controllers and then simply set P3D to the default config.

Nope. Doesn't work with that, either.
So, having spent an hour trying to sort that out, I can now look forward to about an hour to 90minutes actually manually configuring it all again tomorrow. In fact, double that, as I also need to do it for my Thrustmaster HOTAS, too (as a back-up) - as that xml also won't install.