Méthode .htaccess
RewriteEngine On
RewriteCond %{HTTP_HOST} !^www.[^.]+.[^.]+$
RewriteRule ^(.*) http://www.%{HTTP_HOST}/$1 [QSA,L,R=301]
RewriteEngine On
RewriteCond %{HTTP_HOST} !^www.[^.]+.[^.]+$
RewriteRule ^(.*) http://www.%{HTTP_HOST}/$1 [QSA,L,R=301]
