Fantastico shows error ‘You cannot install more than one script in the root directory of a domain’

In order to solve this issue you should follow these steps:

 
1. Log in cPanel and click on File Manager;

 
2. Navigate to .fantasticodata in your Home Directory;

 
3. Delete the file installed_in_root.php.

 
This will ensure there is no Fantastico information remaining from previous installations.