How to make direct link working?

If I go directly to my web page: http://www.uni-action.com/, that work.
If on that web page I click on menu Telechargement that will open http://www.uni-action.com/telechargement
but If I try to refresh I get an error page not found
IF I try to put http://www.uni-action.com/#telechargement , that work but I cant change the page name for that so.
How make my link directly working?