Error: "Another version of this product is already installed"

Error: "Another version of this product is already installed. Installation of this version cannot continue. To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel."

I have Cabal Unlimited Instaled,but I want Cabal Elite too...and I can't instal...give me theat error. How can I change product key...or what can I do?
Thx!

remove the unlimited cabal registry then you can install the other version too

Right click installer > Extract here using WinRAR, job dun :V

SAME ERROR BUT WHEN I TRY TO REMOVE THE CABAL IN THE UNINSTALLER THIS MESSAGE COMES OUT ""Could not access to network location "" plss help me!