Goodnight,
after a lot of research, tests, by uninstalling and reinstalling GSX, with your advice, I found myself searching what could produce this breakdown. I knew that until 08 December, everything worked well, (despite the compatibility mode, lol) so I started to explore the updates installed since that date.
And then I noticed that he had installed two times the same shift (Microsoft Visual C ++ 2012 redistributable 11.0.60610) but a x 86 for the 64 bit (like my system) and an a x 64.
I uninstalled this x 64 which does not seemed to be in its place and tried following FSX, and BINGO, GSX to regenerated the cache of airports. And obviously works. I am a flight on to be certain, but I think I can say that the problem is solved.
Maybe leave it in sight in case another person meet this problem.
Thanks again for your help.
Gilles.