Can I use upgrade media to install Windows 7 on a computer that doesn currently have Windows installed on it?
Windows 7 upgrade media was designed to be used on a computer that has Windows XP or Windows Vista installed on it. You can use upgrade media to install Windows 7 on a computer that doesn’t have Windows XP, Windows Vista, or any version of Windows installed on it by starting (or booting) your computer from the Windows 7 DVD and performing a custom installation. However, you won’t be able to activate Windows 7, which validates that you have a genuine copy of Windows and allows you access to all the features. For more information about activation errors, see Windows 7 activation error: invalid product key and Windows 7 activation error: 0xC004F061. We recommend that you install Windows XP or Windows Vista before installing Windows 7 using upgrade media. Before you attempt to install Windows 7 using upgrade media on a computer that doesn’t have Windows on it, see Installing and reinstalling Windows 7.