[Silhouette]

Windows XP might have been available for a decade, but you have to consider that Vista flopped and Windows 7 only arrived around 3 years ago.

That means large numbers of organisations were still installing Windows XP as their standard desktop around 3 years ago, and possibly even more recently than that since they wouldn't necessarily have evaluated Windows 7 and set up to migrate to it from day 1.

Moreover, the days of upgrading hardware every 2-3 years are gone, at least in typical office environments that aren't really pushing the performance limits of a typical office PC any more.

In other words, for large organisations that keep relatively up-to-date, it's still entirely possible that they have a lot of WinXP machines still around today, even if their newer machines are on Windows 7 now.