When you are hosting with Apache on an OSX Server box, the default setting is to not allow .htaccess files the ability to use mod_rewrite.
Sadly, no error is thrown to let you know you have no permission to call and use mod_rewrite – it just fails silently.
So, if you are using Joomla and trying to use Search Engine Friendly (SEF) URL’s, you must go in and edit the httpd.conf file for the slice that you are using.
Config files are normally stored in /etc/apache2/sites
Open up the config file, and find the line that says:
Make it say:
AllowOverride FileInfo Options