I have done this, and, but...
I did a migration from XP home to Windows 7 pro about three months ago. It did require some simplification of my Win XP system, which was on two hard drives, to get all the key programs on one. It did require the scary situation of killing all anti-virus ands firewall programs while remaining on live internet because Zinstall central has to validate the software (at that point you didn't pay until it worked). Now I do have a very workable XP virtual machine for old tax programs, games, and such inside the Win7 machine. Amazing! Drawbacks: nothing inside the virtal machine communicates with the internet, so the old email settings don't work. There are ways to move documents from the old desktop to the new, so I can probably export the settings, but nothing on the old machine upgrades. This is safe, since the security of the WIN7 machine takes care of it, but it set a deadline for real migration of most things. I suppose this happens because the virtual machine doesn't really exist in a way that registers on the Internet? More interestingly, the former machine, which still runs, will update and communicate with the Internet,except for microsoft update -- probably the migration canceled out the registration of that machine's Win XP?
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