I'm sorry, but you simply CAN'T say, on Christmas Eve, after having disappeared for months, that you now have a problem that you need to be fixed ( which is created by something that obviously wasn't present when you bought the product, because you can't buy it without having the software running), that we don't do adequate product support because, saying so, you are only embarassing yourself, because everybody knows we have the best support around and the fastest reaction time ever. It's YOU that decided to stay "months" without using the program but, if you don't say it, how are we supposed to know you still can't use it ?
So, please, save yourself from trying to compare to any other developer, because we don't need to learn anything from anyone, when customer support is involved.
Now, let's try to understand what your local problem is. And please, don't disappear for 9 months this time around...
Ok, as said before, re-installing flight simulator NUMEROUS times has not helped.
And, as I've said instead, it's not sure that reinstalling FSX would have fix it either, but in some cases this would be related to Windows.
When YOU (you did this, have you realize it or not ?) decide NOT TO TRUST a module, it's a two-fold process. The first part you are telling *Windows* itself not to trust a module and if you say "no", FSX will not ask further. If you say "Yes" to Windows, you can still say "No" in FSX and THIS answer is the one that gets recorded by FSX.
For the Windows part of the issue, you can try changing this registry key:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\WinTrust\Trust Providers\Software Publishing
using REGEDIT
The default value is 0x23c00 (23c00 hexadecimal). If you see any other value, try to change it to back 0x23c00. We don't have any idea which other software might have change this, but it's entirely unrelated to flight simulation, and of course a Windows reinstall would have fixed it, but it's worth trying this first.