When I travelled to the AutoCAD bloggers preview I took a Tablet PC from work. I wanted to have the beta AutoCAD 2010 available but didn't want to "pollute" a production machine with test code. The solution was to install Microsoft Virtual PC and a XP Pro just for the beta. The Tablet runs Vista so for a week I was running AutoCAD Gator on an XP VM in Vista. It worked fine other than having no hardware acceleration which was hardly a problem on the Tablets integrated graphics.
Until I saw Mauricio Freitas' post today I didn't know Microsoft are planning to do the same in Windows 7. Although it's a hardware VM, rather than software, loading a virtual machine with your old operating system is one way to deal with legacy! If you launch a legacy application that demands XP it gets what it wants, virtually.
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