For whatever reason, if you wish to not allow the http://1.2.3.4/~username method of viewing a website, you can do so by removing the lines:
AliasMatch ^/~([^/]+)(/.*)* /home/$1/public_html$2
from the apache VirtualHosts, by editing the templates.1) Type:
cd /usr/local/directadmin/data/templates/custom
cp ../ips_virtual_host.conf .
2) Type:
echo "action=rewrite&value=ips" >> /usr/local/directadmin/data/task.queue
3) Edit:
/etc/httpd/conf/extra/httpd-vhosts.conf
and again, remove the AliasMatch line.