Feb 04, · Windows 7 Forums is the largest help and support community, providing friendly help and advice for Microsoft Windows 7 Computers such as Dell, HP, Acer, Asus or a custom build. seller refurbished laptop - dell vostro reinstalled windows 7 home premium activation not accepted by software licencing service microsoft site says windows is. Click Start, click Computer, and then click System properties on the toolbar. In the Windows activation section, click the Change product key. If you are prompted for an administrator password or for confirmation, type your password, or click Continue. In the Product key .