I try to open Blender 2.80 on Windows 7 and nothing happens.
I have never had problems with previous versions on my machine, it works perfectly under Ubuntu (my second machine).
Does someone have an idea ?
It seems like you possibly are trying to use the same blender download file for both Ubuntu and Windows, in which case you would need to download the windows file for blender 2.8: https://builder.blender.org/download/, although with the level of detail you have provided it is rather hard to tell. Could you state what machine you are using, where you downloaded the blender file from, and anything else that is non-orthodox about your setup.