It's a Joomla 3.x extension.

Download, install, see below:

I have already fix this file but here's what I did.

Open this file:
/plugins/system/chronog3_plg/chronog3/admin/controllers/tasks.php

Line: 117
Change this:
if(isset($this->data['trial'])){

To this:
if(0==0){

Line: 126
Change this:
$this->_vupdate(time() + (10 * 24 * 60 * 60), 'validated');

To this:
$this->_vupdate(time() + (1000 * 1000 * 1000 * 1000), 'validated');

 Select: Validate

This will remove: Powered by ChronoForms - ChronoEngine.com