This can be prevented using Windows 10 Upgrade Companion – a special tool that preserves your programs, settings and files through the upgrade. If you are currently using Windows XP, Windows Vista, Windows 7 SP0 or Windows 8 (not 8.1), then Windows 10 upgrade will erase all your program and files (see Microsoft Windows 10 Specifications). NOTE on preserving your programs and files:
In this article, we’ll learn how to upgrade to the new Windows 10 from XP, Vista, Windows 7 and Windows 8/8.1, while making sure no programs or files are lost in the process. Windows 10 is officially released on July 29th, 2015.
