1. Without mod_rewrite solution:
Just place this code on top of your .htaccess
or in Apache config:
DirectoryIndex index.html index.php
2. mod_rewrite solution:
Enable mod_rewrite and .htaccess through httpd.conf
and then put this code in your .htaccess
under DOCUMENT_ROOT
directory:
Options +FollowSymLinks -MultiViews
# Turn mod_rewrite on
RewriteEngine On
RewriteBase /
RewriteRule ^(abx/xyz)/?$ $1/index.php [L,NC]