Finally i Used auto installer and i got Joomla 3.1 installed !! here's my new problem : i tried to Use the SJ Template it was Uploaded and installed Succesfully, but when i opened my home i got this Error : Fatal error: Class 'YTTemplateUtils' not found in /home/mydir/public_html/templates/sj_joomla3/html/com_content/featured/default.php on line 37 after i saw that i did Upload and install the YT Plugin, still i get the same Error message !! any ideas?!