So far, Microsoft (MSFT 2.51%) Windows 8 isn't working. The operating system is tasked with reinvigorating the stagnant PC market. One of the biggest challenges that Microsoft is pursuing is the dramatic reinventing of Windows 8's interface, a tall order when you consider how many users have become accustomed to Windows over the decades.

Perhaps the most controversial move was the elimination of the Start Menu that we all know and love. The Start Menu originally debuted in 1995 alongside Windows 95 nearly two decades ago. In Windows 8, the Start Menu has been replaced by the Start Screen that features its characteristic live tiles to access various apps.

The lack of a Start Menu is confusing for some consumers -- not too surprising when you think how long they've been trained to go there. Shortly after launch, user interface design specialist told CNET that Windows 8 "smothers usability" and even experienced users had problems figuring it out.

Microsoft now has 1.5 million more reasons to bring back the Start Menu: Pokki.

Pokki is a third-party application launcher for Windows 8 that offers a substitute Start Menu that it calls the Pokki Menu.

Source: Pokki.

It looks and functions just like the traditional Start Menu and also offers options that allow users to bypass the default "Metro" interface and boot directly to the warm embraces of the familiar desktop. The newest version allows you to use the Windows 8 logo instead of Pokki's so it even looks like it's part of the OS.

Pokki has now announced that it's reached over 1.5 million downloads, proof that a large number of Windows users want to go back to the way it was.

Microsoft recently announced 60 million Windows 8 licenses sold. Those downloads would only comprise 2.5% of those licenses sold, but remember that Microsoft's figure represents both upgrades and OEM sales. A lot of the PC sales in the fourth quarter were clearing out Windows 7 inventory, so it's hard to estimate Windows 8 sales to end users, but they're likely much less than 60 million. That also means that the Pokki penetration among the Windows 8 installed base is higher.

Pokki also has its own app store, which could divert traffic and dollars away from the Windows Store, so Microsoft should take note of its growing popularity.

The new interface is a big risk that Microsoft is taking -- a bet that might not be resonating with PC users.