Win 8 system downgrade problem

a, buy pre-installed Win 8 Professional PC
b, can be downgraded to Win 7 Professional Edition or Vista Business Edition
c, upgrade to Win 8 Professional Edition when needed Since the license has been obtained, the upgrade is free and the user can upgrade at any time.
Note that you need a Win 7 Professional or Windows Vista Business Edition media CD to achieve a downgrade from Win 8 Pro.
Understanding downgrade rights:
Downgrade rights details and frequently asked questions:
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