Hi, just made a back up u1.2 409beta copy and put it into western digital 250g hard drive, tried to open exe but it wont open game, i can open, edit files /folders etc. Made shortcut for switcher as well and it works but wont run exe to start. Any ideas of what i might need to do? regular game is in c program files etc, copy is in J drive and renamed as well.

Hmm, that's odd, it should work just fine. Are you using the exe in the game folder or the shortcut?

Ive tried both, and i just updated my net framework to 2.0 so it works on other c drive version just fine.

dotnet is not used by IL-2. If you have an ATI card and use CCC then it is used by that, but not essential. You could use Ray Adams Tray Tools instead of CCC and loose the dotnet crap altogether. What do you mean with "other c drive version" ?
Do you mean you have a second install of
IL-2 located on your C: drive and that works fine (as it should)?