Microsoft updated Microsoft Select License, Open License, Original Equipment Manufacturer (OEM) License, and Full-Packaged Product (FPP) License Downgrade Rights documentation to also refer to Windows 7. “Can I downgrade my OEM version of Windows 7 Professional to Windows XP Professional? For a limited time of 18 months after the general availability of Windows 7 or the release of a Windows 7 Service Pack, whichever is earlier, the OEM license of Windows 7 Professional and Windows 7 Ultimate will include downgrade rights to Windows XP Professional. After that period the OEM license will enable downgrade rights to Windows Vista Business,” Microsoft explained.
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