If you get following error while running webalizer updater :Error: Unable to lock DNS cache file /usr/local/psa/var/webalizer.cachethen do as follows:
rm -f /usr/local/psa/var/webalizer.cache
touch /usr/local/psa/var/webalizer.cache
chown root:root /usr/local/psa/var/webalizer.cache
chmod 644 /usr/local/psa/var/webalizer.cache
stat /usr/local/psa/var/webalizer.cache