Hello Pursuivant,
Thank you for your quick answer. I agree with your that there is some device driver conflict, I just cannot pin-point it.
Just to clarify, before installing the Logitech wireless keyboard I had only the laptop standard keyboard (PS\2). IL2 1946 (patched to v4.12.2) worked perfectly with the standard laptop keyboard, joystick (CH Combatstick) & rudder (CH pedals).
When I first connected the Logitech wireless keyboard windows recognized and installed the drivers automatically and it worked in IL2. After that either keyboards (laptop standard PS/2 & the USB wireless one) stopped working in IL2. In the end I've installed the Logitech drivers, but unfortunately with no effect.
Even after uninstalling/disabling the USB keyboard drivers IL2 is not responding to the laptop standard keyboard input.
To follow your advice:
1. - reg cleaninig. Done (CCleaner + Norton Registry cleanup) => no effect;
2. - win updates. I have the latest windows 7 updates (I run win update regularly);
3. - keyboard drivers. I've downloaded the latest logitech drivers => no effect;
4. - IL2 patches. When IL2 stopped responding to keyboard inputs it was patched to v4.12.2. I think the problem is independent of IL2 patch version. As I mentioned same thing (standard keyboard not recognized) happens for a fresh install of IL2 Pacific Fighters (from CDs). I'm thinking to keep the IL2 1946 install until I solve the problem and then I'll update to the latest patch. Anyway, I'll give it a try (patch to v4.12.2).
5. - Install the old drivers. The wireless keyboard did not come with installation CD. They provided a web link for drivers installation so I guess no older drivers.
In IL2 setup->joystick tab->advanced the joystick is set as preferred control device, but no effect (joystick is recognized in the game but the keyboard is not).
So, no joy so far
Thank you again for your help, hopefully we'll figure it out.