One of the tools Microsoft developed to aid companies in transitioning from Windows XP to Windows 7 was a free virtualized copy of Windows XP. Once downloaded and installed, users with XP-specific applications could run them seamlessly alongside Windows 7. Inventing such a practical, useful tool apparently frightened someone at Microsoft and XP Mode was hamstrung with a requirement that crippled its usefulness. In order to use Microsoft's free virtual OS, the CPU in question had to support hardware virtualization.Windows
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