Hi all, You have to perform a clean installation of Windows 7 when using the upgrade version to upgrade from Windows XP. But, if you install the Upgrade version of Windows 7 Home Premium on a Windows XP Pro system on a different partition, does doing so invalidate your Windows XP Pro license and make it impossible to have a dual-boot system unless you buy a new XP license? No one on the web seems to know for sure. The licence agreement for Win7 says that this is the case. If you upgrade from Windows XP to Win7, you lose Windows XP.