Disable the User Account Control (UAC) feature prior to installation (this requires restarting your system). To do this:

1. Type MSCONFIG in the Start menu > Start Search text box.
2. Click the Tools tab. Scroll down and select "Change UAC Settings".
3. Click Launch.
4. A window opens. Disable UAC and close the window.
5. Close MSCONFIG and restart your system to apply the changes.