When Microsoft introduced Windows Vista, many users were very upset to discover that some of their older applications did not work correctly in Vista (some application vendors did not upgrade their applications for Vista, or charged more for new versions than users were willing to pay). As such, a lot of users (and businesses) cited this as a reason for not upgrading to Vista.
Microsoft realized the severity of this problem and hopes to solve it in Windows 7 by providing a feature known as Windows XP Mode (XPM). XPM lets you run your legacy Windows XP applications inside a virtualized environment, either from within a virtual XP window or as a seamlessly integrated application within Windows 7.
A virtualized environment creates an environment that mimics an actual computer, so in XPM, you’ve got a copy of Windows XP that thinks it’s got a computer all to itself. As a result, applications that run under XPM are similarly fooled: as far as they are concerned, they are running under Windows XP, and do not interact directly with Windows 7.
XPM is available for the following Windows 7 editions: Professional, Ultimate, and Enterprise. If you don’t find it on your Start menu, you’ll need to get two things: Windows Virtual PC and the Windows XP Mode package. If Windows Virtual PC is already installed, you can skip ahead to the Windows XP Mode package instructions.
To get Windows Virtual PC, head over to http://www.microsoft.com/windows/virtual-pc/download.aspx ...