Handler PHP_via_FastCGI has a bad module FastCgiModule in its module list

I have seen that a lot of people visit this site when searching for:

Handler "PHP_via_FastCGI1" has a bad module "FastCgiModule" in its module list.

So, here's how to fix it.

1. Go to Control Panel -> Programs and Features -> Turn Windows features on or off

2. Scroll to Internet Information Services -> World Wide Web Services -> Application Development Features

3. Turn on CGI

4. Wait a bit

5. Enjoy

For more information how to configure PHP on IIS visit Installation on Windows systems on php.net.