See here How to Patch Windows Vista to Enable Custom Themes (Visual Styles) [link]
Once you've done that, reboot, then follow the directions in the Read Me file. (This says, basically, put the Windows 7 folder under C:\WINDOWS\RESOURCES\THEMES. Go into the Windows 7 folder, double-click the msstyle file. This will bring up the Appearances dialogue. You will see TWO Aero themes. In the list, the top-most one is the Windows 7 theme.
Author: giannisgx89 | Website: deviantart.com
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