Remove from the GUI:

rm -fr /usr/local/cpanel/3rdparty/installatron
rm -f /usr/local/cpanel/whostmgr/addonfeatures/installatron
rm -f /usr/local/cpanel/whostmgr/addonfeatures/itwidget
rm -f /usr/local/cpanel/whostmgr/docroot/cgi/addon_installatron.cgi
rm -f /usr/local/cpanel/base/frontend/*/dynamicui/dynamicui_installatron.conf
rm -f /usr/local/cpanel/base/frontend/*/dynamicui/dynamicui_itwidget.conf
perl -pi -e 's/_in.+\s*//g' /root/cpanelbranding/*/dynamicui.conf
perl -pi -e 's/_in.+\s*//g' /home/*/cpanelbranding/*/dynamicui.conf

Delete the core:

rm -fr /usr/local/installatron
rm -fr /var/installatron
rm -f /etc/cron.d/installatron

Delete user install data (be careful!):

rm -fr /home/*/.installatron

Remove from the GUI:

rm -fr /usr/local/directadmin/plugins/installatron

Delete the core:

rm -fr /usr/local/installatron
rm -fr /var/installatron
rm -f /etc/cron.d/installatron

Delete user install data (be careful!):

rm -fr /home/*/.installatron

Remove from the GUI:

rm -fr /usr/local/interworx/modules/installatron

Delete the core:

rm -fr /usr/local/installatron
rm -fr /var/installatron
rm -f /etc/cron.d/installatron

Delete user install data (be careful!):

rm -fr /home/*/.installatron

For Plesk Linux/Unix servers, note that the the directories /usr/local/psa and /var/www/htdocs may be different on your server.

Remove from the GUI:

perl -pi -e 's!<itronblock1>.+?</itronblock1>!!' /usr/local/psa/admin/plib/templates/modules.tpl
rm -fr /usr/local/psa/admin/htdocs/modules/installatron

Delete the core:

rm -fr /usr/local/installatron
rm -fr /var/installatron
rm -f /etc/cron.d/installatron

Delete user install data (be careful!):

rm -fr /var/www/htdocs/*/.installatron

Remove from the GUI:

rd \"%plesk_dir%\\admin\\htdocs\\modules\\installatron\" /S /Q

Delete the core:

rd \"%itron_dir%\\Data\" /S /Q
rd \"%itron_dir%\\etc\" /S /Q
rd \"%itron_dir%\\lib\" /S /Q
\"%itron_dir%\\uninstall.exe\"

Delete user install data (be careful!):

FOR /D %i IN (\"C:\\inetpub\\vhosts\\*\") DO rd \"%i\\.installaton\" /S /Q

Delete the core:

rd \"%itron_dir%\\Data\" /S /Q
rd \"%itron_dir%\\etc\" /S /Q
rd \"%itron_dir%\\lib\" /S /Q
\"%itron_dir%\\uninstall.exe\"

Remove from the GUI:

rm -f /usr/local/lxlabs/*/etc/flag/installatron.flg

Delete the core:

rm -fr /usr/local/installatron
rm -fr /var/installatron
rm -f /etc/cron.d/installatron

Delete user install data (be careful!):

rm -fr /home/*/.installatron