If installation and analysis takes longer, or is that you simply see a mistake message or maybe a perpetual install process, it might be for an additional reasons:
A person the administrator for that computer or else you do not possess administration rights to put in new programs. Administrator rights usually connect with computers that have more than one user that logs in to the computer.
The pc browser or operating system is just not compatible. See set of compatible browsers. This may occur with new browser versions which have not even been verified.
The Active-X/Java add-in permissions are blocked by browser, firewall, or user