If you don’t have a default index page in any of your directories, most servers, by default, will display a listing of all of your files and directories(folders), which can be a potential security risk.
To fix this, simply add the following to your .htaccess file:
Or, if you find that you aren’t getting the directory listing, and you have confirmed that you do not have an index page, and would like the directory listing for whatever reason, try adding this to your .htaccess file:
If you’re hosted with BlueHost or another host with cPanel, they have a nifty little tool that will allow you to tweak this a bit more. See: http://helpdesk.bluehost.com/index.php/kb/article/000414