How to Force the OEM Version of Windows Vista to Install as an Upgrade
- 1). Insert the Vista installation disk into your computer.
- 2). Click on the "Install Now" button that appears onscreen.
- 3). Select the option to "Get Important Updates."
- 4). Enter your product key and push the "Accept" button to accept the EULA.
- 5). Select the option to perform an "Upgrade" installation.
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