Microsoft has officially announced that they plan to bring back the Start Menu from Windows 7. This update may only be available for Windows 8.1. Microsoft continues, saying they plan to run all apps within a window, instead of using the full screen. This update will eventually be available using Windows Update.
There is a program available now that offers a Start Menu that looks nearly identical to the old Windows 7 menu, but it has to be purchased one time for $4.99. A link has been provided that will guide you (with pictures) on how to install and get the paid Start Menu working. Please make sure to stop at "Step 2: Install Windows 7 Aero Theme." The next step has nothing to do with the Start Menu, it is only for making your theme transparent. It is a very advanced setup and is not reccomended.
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Instructions for paid Start Menu - Click Here