before anything i searched everywhere and tested everything
but still not working
i install php5-fpm and nginx
when i open localhost in browser i see this page :

Welcome to nginx!

so its working now configuring php5-fpm with nginx :

/etc/php5/fpm/pool.d/www.conf

  user = www-data

  group = www-data

  listen = /var/run/php5-fpm.sock

  listen.owner = www-data

  listen.group = www-data

  pm = dynamic

  pm.max_children = 5

  pm.start_servers = 2

  pm.min_spare_servers = 1

  pm.max_spare_servers = 3

  chdir = /

all other lines are commented and this is the nginx conf :

  upstream php {

        server unix:/var/run/php5-fpm.socket;

  }



server {

listen 80 default_server;

listen [::]:80 default_server ipv6only=on;



root /usr/share/nginx/html;

index index.html index.htm index.php;



# Make site accessible from http://localhost/

server_name localhost;



location / {

    # First attempt to serve request as file, then

    # as directory, then fall back to displaying a 404.

    try_files $uri $uri/ =404;

    # Uncomment to enable naxsi on this location

    # include /etc/nginx/naxsi.rules

}



# Only for nginx-naxsi used with nginx-naxsi-ui : process denied requests

#location /RequestDenied {

#   proxy_pass http://127.0.0.1:8080;    

#}



#error_page 404 /404.html;



# redirect server error pages to the static page /50x.html

#

#error_page 500 502 503 504 /50x.html;

#location = /50x.html {

#   root /usr/share/nginx/html;

#}



# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000

#

location ~ .php$ {

try_files $uri =404;

    fastcgi_split_path_info ^(.+.php)(/.+)$;

    fastcgi_pass unix:/var/run/php5-fpm.sock;

    fastcgi_index index.php;

    include fastcgi_params;



}



# deny access to .htaccess files, if Apache's document root

# concurs with nginx's one

#

#location ~ /.ht {

#   allow all;

#}

}

the problem is when i try to run php files nginx will download php file instead of executing it