Operation Desert Storm: 30th Anniversary Edition

[Menrva]

1 hour ago, kekosam said:

Hi.

They're merged in a single installation. If you call one of then, you can fly any mission of all. 

I've already uninstalled and reinstalled a lot, and the problem still goes on. 

I have no clues as to why it doesn't work on your end. The installer queries Windows' registry keys to read the path of your SF2 installation (in particular it looks for the InstallLocation key, check image below).

Once the path has been retrieved, the installer then looks for the stock game files in the game's folders, if one of the required .CAT archives is missing it cannot proceed with proper installation.

EDIT: Actually, on a closer look to your screenshot, it seems you do not have Strike Fighters 2: North Atlantic. I'm afraid that's one of the required games and you're missing it, the download page clearly states which games are required by the mod.