Microsoft's decision to leave Windows XP users behind, with no easy upgrade path to Windows 7, is, possibly, the sole mistake of an otherwise pitch-perfect product development and launch campaign.

Yes, I know there's precedent for Microsoft not helping customers upgrade from multi-generations-old operating systems. When XP shipped in October of 2001, Windows 3.1 and even Windows 95 were left behind. The exact phrasing Microsoft uses in its literature is: "No Supported Upgrade Paths." When Vista shipped in January 2007, XP had multiple paths, but Windows 2000 (and older OSs) were left out in the cold.

To clarify, Microsoft isn't abandoning these users. The company is simply making it clear that for any user running a Windows operating system older than Vista, there is "no supported upgrade path." That means, of course, that you'll need a clean install to run Windows 7. Look, our tests have shown that Windows 7 is one of the leaner Windows OSs in recent years. It can even run on sub-powered netbooks. So, it'll likely run on your older systems (within reason, of course). However, if you want to move that XP system to Win 7, you'll need to do what Microsoft is calling a "Custom install." Microsoft describes it thusly:

"A custom installation gives you the option to either completely replace your current operating system or install Windows on a specific drive or partition that you select. You can also use Custom if your computer does not have an operating system, or if you want to set up a multiboot system on your computer."

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