Then go to your server and check whether you have ow_updates folder in the root of the software.
if so, please paste it's content here
your server does not meet our requirements and you disable htaccess by renaming it
which is why the site works but not properly. seems like the mod_rewrite module is not installed on your server.
You need to contact your hosting provider to configure server properly or get another hosting provider.
if the htaccess file is not renamed you get the internal server error, most obviously mod_rewrite is not installed: request to configure server according to our requirements http://www.oxwall.org/hosting without renaming .htaccess file