With Windows 8's commercial availability expected before the end of this year, Microsoft finds itself in the tricky position of generating enthusiasm for it without affecting Windows 7 sales.
The difficulty in striking this delicate balance became evident on Tuesday, when Microsoft officials spent the day at TechEd North America promoting Windows 8 in speeches, press conferences and demo sessions, while telling the 10,000 IT pros in attendance that their organisations, if they haven't done so already, should upgrade from Windows XP to Windows 7.
But at the morning keynote, when Microsoft officials made an aggressive case for enterprise adoption of Windows 8, they portrayed Windows 7 as an aging OS designed before key changes in computing happened in recent years.
"Windows 8 is a bold new bet, and it's a generational change in Windows," said Antoine Leblond, corporate vice president of Windows Web Services. "Windows 8 first and foremost is a better Windows than Windows 7."
Leblond said Windows 7 is the last in a line of OSes that began with Windows 95, designed primarily for desktop PCs that are always connected to a power source and act as the main repository for users' applications, data and content.
On the other hand, Windows 8 is designed for the world's shift to mobile devices that run on batteries and to applications and content that live dispersed in a variety of web sites and must be constantly available.
Asked to comment about the way Windows 7 was portrayed in the morning keynote, Erwin Visser, senior director of the Windows Commercial Business Group, said at a press conference later in the day that Microsoft in no way wants enterprise customers to interrupt migrations to Windows 7 from Windows XP.
"In our conversations with enterprises, we don't want to discourage their deployments of Windows 7," he said.
Microsoft will end support for Windows XP in 2014, so migrating to Windows 7 now is the right thing to do, he said, adding that Windows 8 will co-exist side-by-side with Windows 7 in an organisation.
Windows 8 has a new user interface called Metro, which is designed for touch-screen devices, like tablets, but which can also be used with keyboards and mice. The OS will also have a traditional Windows 7-like interface. The Metro interface, whose design and user experience are markedly different from the traditional Windows interface, has been the source of much criticism among beta testers and industry observers, who say it's inconvenient to use with a mouse, and find its overall navigation functionality confusing.
Windows 8 computers based on x86 chips from Intel and AMD will run Windows 7 applications, and will co-exist with Windows 7 machines on enterprise environments, Visser said.
"The investments [enterprise customers] are making today on Windows 7 from a hardware infrastructure and also in application compatibility carry forward into Windows 8," Visser said.
At the same time, Microsoft is "very proud and bullish" about the value of Windows 8 for enterprises, so it expects to see customers upgrade to it from Windows 7, he said.
Some enterprises will opt to do a broad desktop OS upgrade from Windows 7 to Windows 8, while others will deploy Windows 8 initially in a more targeted and limited manner, to, for example, roll out tablet devices to their employees or take advantage of certain OS improvements in security, performance or virtualisation, he said.
Whatever the case, enterprises in general will find that upgrading from Windows 7 to Windows 8 will be significantly simpler and less expensive than upgrading from Windows XP to Windows 7, he said. The XP-to-Windows 7 involves costs related to upgrading PC and other related hardware and to modifying applications, which will be much lower when moving from Windows 7 to Windows 8, he said.
Juan Carlos Perez covers enterprise communication/collaboration suites, operating systems, browsers and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.