The Download button on Doc Scrubber says it is free for business and personal use. When I go to install it, it says it must be purchased. When I hit the button to purchase it it says page cannot be found. If it requires purchase, how do you purchase, what is the price, what are the license terms? If it is not required to purchase, why does it say it requires purchase? Why does it say it is free for both business and personal use?