Well i'd like to undersand the origin of the problem. Alcohol drivers are both a347*.sys files inside \System32\Drivers. For some reasons, they can't be installed properly at the install (even if we click on Next until the end of the wizard), and so the Device manager points an error to that device. And when i open Alcohol, the virtual CD drivers are detected by Windows. Normally, that doesn't happen. So there's an issue with a INF (which is ?) and the drivers ... but i don't see what.