Windows 7 is the only Windows version that is supported, which is why your computer is telling you that it does not have Windows 7.
You will need to purchase a copy of Windows 7 and install it.
P
Bootcamp doens't work on my Windows Vista and I have no idea why. It says that my Mac doens't have a Windows 7.. So my internet doens't work to.. Help me please! (sorry for my English)

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