Just start over, I recommend getting this, it's what I use:
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When you install it all your files will be backed up to a folder called "Windows.000" on your C:\ Drive, in the new installation.
You just have to watch the Windows updates, because one of them is a Genuine checker, and if you install it, and your Windows 7 isn't genuine, you get this permanent text on the bottom-right of your desktop:
Originally posted by another user
Windows 7
Build 7600
This copy of Windows is not Genuine
Anyway, good luck!