French fr_FR.mo translation not working

Hi.

I created a .mo file with translated anglish to french inside.

eveything inside seems ok but when I try to apply it in wordpress it doesn't work..

my WP-LANG setting is set to fr_FR and my .mo is placed into the language folder inside wiki folder. I tried fr_FR.mo Wiki-fr_FR.mo but nothing work.

I need help please