Thank you for your explanation, that's exactly what I wanted to know: could FSUIPC mechanics be somewhat involved in certificate problems. I'm not saying FSUIPC is the cause of the problem, maybe it is SimConnect as you say repairing fsx installation isn't a guarantee of fixing SimConnect's problems.
I'll try that. I did the "reverse thing" running everything else but FSUIPC and it solved my problem... but you're right. To be "sure" that the problem has something to do with FSUIPC (or the way FSUIPC uses SimConnect or any thing else that other addons don't use), I need to try it with only FSUIPC on.
I'll give it a try also.
Here's the log content, just removed some personal information:
********* FSUIPC4, Version 4.88 by Pete Dowson *********
Running inside FSX on Windows 7 --> I'm on win8 x64
Module base=59530000
User Name="XXXXX"
User Addr="XXXXX"
FSUIPC4 Key is provided
WIDEFS7 not user registered, or expired
1015 System time = 01/05/2013 14:20:36
1015 FLT path = "M:\XXXXX\Mes documents\Fichiers Flight Simulator X\"
1031 Trying to connect to SimConnect Acc/SP2 Oct07 ...
1031 FS path = "C:\FSX\"
1296 LogOptions=00000000 00000001
1296 SIM1 Frictions access gained
1296 Wind smoothing fix is fully installed
1296 G3D.DLL fix attempt installed ok
1296 SimConnect_Open succeeded: waiting to check version okay
1296 Trying to use SimConnect Acc/SP2 Oct07
2500 Running in "Microsoft Flight Simulator X", Version: 10.0.61637.0 (SimConnect: 10.0.61259.0)
2500 Initialising SimConnect data requests now
2500 FSUIPC Menu entry added
2515 M:\XXXX\Mes documents\Fichiers Flight Simulator X\Cold & dark setup.FLT
2515 C:\FSX\SimObjects\Airplanes\Carenado C152II\SingleEngineProp.AIR
17062 M:\XXXXX\Mes documents\Fichiers Flight Simulator X\VFR Sion to Les Eplatures.PLN
17062 Weather Mode now = Custom
36359 Aircraft="C152II Calypso"
36359 System time = 01/05/2013 14:21:11, Simulator time = 18:35:09 (16:35Z)
36562 Starting everything now ...
37687 Advanced Weather Interface Enabled
54109 M:\XXXXXX\Mes documents\Fichiers Flight Simulator X\VFR Sion to Les Eplatures.PLN
54109 C:\Users\XXXXX\AppData\Roaming\Microsoft\FSX\Vol précédent.FLT
693625 M:\XXXXX\Mes documents\Fichiers Flight Simulator X\VFR Sion to Les Eplatures.PLN
842562 System time = 01/05/2013 14:34:38, Simulator time = 18:35:07 (16:35Z)
842562 *** FSUIPC log file being closed
Average frame rate for running time of 21 secs = 49.8 fps
G3D fix: Passes 20917, Null pointers 0, Bad pointers 0, Separate instances 0
Memory managed: 15 Allocs, 15 Freed
********* FSUIPC Log file closed ***********
So, if I get you well: If my problem is caused by SimConnect (which is somewhat induced by FSUIPC) and that only a Windows reinstall might fix SimConnect, with no final guarantee that the end result would be the one expected, I think I had better pass the checkrides flights with FSUIPC off and then turn it back again. It's a much more effective solution than a complete system reinstall :razz: And on top of that I know it works!