I had to install wordpress on Ubuntu 12.04.4 x32. and follow the tutorial
*https://www.digitalocean.com/community/tutorials/initial-server-setup-with-ubuntu-12-04
*https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mysql-php-lamp-stack-on-ubuntu
*https://www.digitalocean.com/community/articles/how-to-install-and-secure-phpmyadmin-on-ubuntu-12-04
*https://www.digitalocean.com/community/tutorials/how-to-install-wordpress-on-ubuntu-12-04
*https://www.digitalocean.com/community/tutorials/how-to-set-up-multiple-wordpress-sites-using-multisite

become a WPMU setup, edit the file wp-config.php and htaccess
and make subdomain.domain.com or domain.com/sub, do not work at all.

not Found

The requested URL / sub / was not found on this server.
Apache / 2.2.22 (Ubuntu) Server at Port 80 1** 1** 2** 1**

can you help me to solve this problem?