Turn out the lights, the party’s over. An end of an era has officially come to a close as Microsoft stops sales of Windows 7 Professional, the last version of Windows 7 that it continued providing to OEM system builders a full two years after ceasing sales of the Home Basic, Home Premium, and Ultimate SKUs. Same goes for Windows 8.1—Microsoft

Source: Hot Hardware – Microsoft Ends Windows 7 Professional And Windows 8.1 Sales To OEMs