Question: On my new Ubuntu system, I've managed to get Apache2 up and running for developing my ZendFramework Web Applications...

I've got my `available-sites` config working correctly because I am able to request `localhost` and it servers up the correct `index.html` from my specified directory. 

**Problem :** if I request `index.php`, firefox attempts to download the file instead of running the script.

Any Ideas why this would happen? 

I've added the following to `httpd.conf` but it hasn't helped. 

```
AddHandler application/x-httpd-php .php5 .php4 .php .php3 .php2 .phtml

AddType application/x-httpd-php .php5 .php4 .php .php3 .php2 .phtml

```

Answer: 
If Firefox downloads your PHP files it means that your server doesn't have PHP or the Apache PHP module installed.

Have you installed the Apache PHP module?
If not then install it by typing this into a terminal:

```
sudo apt-get install libapache2-mod-php5

```

And if yes, do you have your index.php located in `/var/www/`?

Make sure to enable PHP with the command

```
sudo a2enmod php5

```
I'll assume you installed PHP already and installed the PHP module for Apache here...

Did you restart apache? If not: `sudo service apache2 restart`

Make sure that your httpd.conf file is also being executed. If necessary, restart it after making an edit that would cause an error on load. If it doesn't fail to restart, it's not running the .conf file.

If the problem still continues, close your browser, reopen it, and clear your cache. It might be the browser just caching the page response.