Joomla 3.x requires magic_quotes_gpc to be turned off in order to function correctly.
On our shared hsting servers we have this option turned on by default and it will not be turned off server-wide.
In order to turn it off for your domain, you need to place (or edit the existing one) .htaccess file in the root folder of your domain (public_html).
in the .htaccess file you need to plac the following code on the separate line:
php_value magic_quotes_gpc off
This will fix your Joomla installation.