Nginx serves .php files as downloads, instead of executing them

Try this:

1. Edit /etc/nginx/sites-available/default

2. Uncomment both listen lines to make nginx listen on port 80 IPv4 and IPv6.

   listen   80; ## listen for ipv4; this line is default and implied
   listen   [::]:80 default_server ipv6only=on; ## listen for ipv6
   

3. Leave server_name alone

   # Make site accessible (...)
   server_name localhost;
   

4. Add index.php to the index line

   root /usr/share/nginx/www;
   index index.php index.html index.htm;
   

5. Uncomment location ~ \.php$ {}

   # pass the PHP scripts to FastCGI server listening on (...)
   #
   location ~ \.php$ {
           try_files $uri =404;
           fastcgi_split_path_info ^(.+\.php)(/.+)$;
           # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini
   
           # With php5-cgi alone:
           #fastcgi_pass 127.0.0.1:9000;
           # With php5-fpm:
           fastcgi_pass unix:/var/run/php5-fpm.sock;
           fastcgi_index index.php;
           include fastcgi_params;
   }
   

6. Edit /etc/php5/fpm/php.ini and make sure cgi.fix_pathinfo is set to 0

7. Restart nginx and php5-fpm sudo service nginx restart && sudo service php5-fpm restart

I have just started using Linux a week ago, so I really hope to help you on this. I am using nano text editor to edit the files. run apt-get install nano if you don't have it. Google on it to know more.

I had similar problem which was resolved by emptying the browser cache (also worked fine with different browser).

You need to add this to /etc/nginx/sites-enabled/default to execute php files on Nginx Server:

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

    root /usr/share/nginx/html;
    index index.php index.html index.htm;

    location ~ \.php$ {
        try_files $uri =404;
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }
}

I see a lot of solutions above and many worked correctly for me, but I didn't understand what they were doing and was worried of just copy pasting the code, specifically, fastcgi. So here are my 2 cents,

1. nginx is a web server (and not an application server) and thus, it can only serve static pages.
2. whenever, we try rendering/returning a .php file, for example index.php, nginx doesn't know what to do, since it just can't understand a .php file (or for that matter any extension apart from a select few like .html, .js etc. which are static files)
3. Thus in order to run other kinds of files we need something that sits between nginx and the application (here the php application). This is where common gateway interface (CGI) comes in. It's a piece of software that manages this communication. CGIs can be implemented in any possible language Python (uWSGI), PHP (FPM) and even C. FastCGI is basically an upgraded version of CGI which is much much faster than CGI.

For some, servers like Apache, there is built in support to interpret PHP and thus no need for a CGI.

This digital ocean link, explains the steps to install FPM pretty well and I am not writing the steps needed to solve the issue of php files getting downloaded instead of rendering since the other answers IMHO pretty good.

Update nginx config /etc/nginx/sites-available/default or your config file

if you are using php7 use this

    location ~ \.php$ {
            include snippets/fastcgi-php.conf;
            fastcgi_pass unix:/run/php/php7.0-fpm.sock;      
    }

if you are using php5 use this

    location ~ \.php$ {
            include snippets/fastcgi-php.conf;
            fastcgi_pass unix:/run/php/php5-fpm.sock;
            fastcgi_index index.php;
            include fastcgi_params;
    }

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