From Pulsed Media Wiki
Removing an user with previous versions of PMSS was a manual task. Both methods are described here. In both methods remember to remove DNS entries if you are not using wildcard records.
Confirm deletion, and script will remove the user
Manual user removal
cd /home killall -9 -u USERNAME userdel USERNAME vim /etc/lighttpd/lighttpd.conf /etc/init.d/lighttpd restart htpasswd -D /etc/lighttpd/.htpasswd USERNAME rm -rf USERNAME
When you open lighttpd conf in vim type: /USERNAME[enter] and you will likely end up on first line of user VHOST configuration, then type: d9[arrow down] to delete that section. save & exit by typing: :wq[enter] htpasswd -D line is optional, but recommended.