I believe what patio meant to say is there is no DIRECT upgrade path from XP to W7
I think people may be getting caught between two slightly different meanings of the word 'upgrade'. In ordinary English, to upgrade means to choose to improve something or bring it up to date. You might upgrade a cable TV package to a level with more channels, or an airline ticket from tourist to business, or upgrade the comfort level of a hotel room you have booked, or you might decide to upgrade from a 14 inch CRT to a 42 inch plasma TV. Or indeed to replace an old version of software with a newer one, or go from a free version to a premium one. Very often the software supplier will make a new version cheaper or free for owners of previous versions. With operating systems this may involve nuking the earlier version and completely replacing it with the new one, or sometimes (and here comes the other meaning of the word) with some Microsoft Windows versions, it is possible to transform an installation of an earlier or lower level version to a later or higher level one, leaving some or all installed programs, user files (documents, pictures, music, whatever) and some settings and stuff (e.g. bookmarks) intact. If you pay the lower price for an upgrade license the installer wants to see proof that you own the 'qualifying product'. Either it is there on the hard drive or it will ask to see the original OS CD or DVD. Microsoft does not make this type of 'upgrade' available to users of every version. There is a list of supported (and unsupported) upgrades with Windows 7 as the target here:
http://technet.microsoft.com/library/dd772579.aspxIf an upgrade of this type is supported, there is said to be an 'upgrade path' in existence. For example there are paths from Vista Business to Windows 7 Professional, Enterprise or Ultimate, and from Vista Enterprise to Windows 7 Enterprise (only). There is no 'upgrade path' - using the Microsoft meaning - to any version of Windows 7 from any version of Windows XP. Of course that does not mean you can't put Windows 7 on a PC that is already running Windows XP. It just means that you can't buy a cheaper W7 license and keep all your installed apps in place. Hence people's curiosity about the "preexcisting OS disk". (I wonder if it was titled thus?) There is an Easy Transfer Wizard on the Windows 7 DVD that can look for non-program data in your old XP installation and shove the stuff you choose to keep into a .MIG file on an external hard drive so you can get at it after the Windows 7 installation is complete. Or you can do it manually first.
I do feel that using LMGTFY links should be done very sparingly; it can so easily seem like annoying sarcasm and a put-down, and is hardly likely to encourage a flood of help.
