The .htaccess
file turns off the display_errors. That's why you are getting a blank response.
Change it as shown below
DirectoryIndex index.php
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteRule ^$ index.php [QSA,L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php [QSA,L]
</IfModule>
<IfModule mod_php5.c>
php_flag display_errors On
</IfModule>
Then you will get the clue!