I recently came across a client who had a problem deleting users from their Joomla site.  When tried to delete a user they keep on getting a blank page and didn’t delete the users.   The error message looked like:

PHP Warning: Missing argument 2 for plgUserDeleteUser::onBeforeDeleteUser() in /home/#####/public_html/plugins/user/deleteuser.php on line 26
PHP Warning: Missing argument 3 for plgUserDeleteUser::onBeforeDeleteUser() in /home/#####/public_html/plugins/user/deleteuser.php on line 26
PHP Warning: Missing argument 2 for plgUserDeleteUser::onBeforeDeleteUser() in /home/#####/public_html/plugins/user/deleteuser.php on line 26
PHP Warning: Missing argument 3 for plgUserDeleteUser::onBeforeDeleteUser() in /home/#####/public_html/plugins/user/deleteuser.php on line 26

You can fix this problem easily following these steps:

1.  Go to your Joomla Administrator backend.

2.  Click on Tools, “install/uninstall”, Plugins

3.  Uninstall the “DeleteUser” plugin.

Logout and refresh your site.  You should be able to delete users from your Joomla site now.