Open up conf/settings.php and add this line:
$Configuration['URL_BUILDING_METHOD'] = 'mod_rewrite';
First of all I want to make it clear that having a MySQL database without a password set (on your root account) is a very very bad idea. However I wanted to set it up on my home machine which has XAMPP installed. And XAMPP by default creates a root account for MySQL without any password. I had several applications installed in that configuration. So I tried to do the same with Vanilla. However Vanilla wouldn't allow me to do so. Actually the setup goes fine but then it refuses to show claiming failure to connect to the database. Here is a simple solution.
.htaccess is a web server directive file populalrly used in Apache Web Server in Linux / Unix environment. In windows environment there is a simple way to enable and use .htaccess. Additionally it allows you to create nice permalinks for software like WordPress or phpBB.