AOE2 Beta don't launchs

I have the beta version, I played 5 times, the last day, when I tried to launch it, Steam downloaded it again as if it wasn’t installed (but it is). Now, I double click on the icon or start on the Steam menu and Steam does the same thing it always does, but the game never starts.

i have the same problem , i received a beta key i followed the guide step by step i have no error messages when i launch the game it doesnt work

Not same problem i think, u need step 7 of the installation instructions