The unprecedented deal kicks off when Windows 10 officially releases later in 2015, and runs for one year after that. During those 12 months, users can upgrade free of charge. Microsoft, however, dodged a question Wednesday at its Windows 10 presentation about what will happen after the year's expiration, saying it had not yet worked out those details.
People with Windows Phone 8.1-powered smartphones will be able to upgrade to Windows 10 free of charge during that same 12-month post-release period.
Microsoft also confirmed what had it had only hinted at before, that Windows 10 will be a long-term operating system that will be regularly updated with features and functionality, also free of charge.
"This is so much more ... than a free one-time upgrade," said Terry Myerson, the Microsoft executive who heads the operating systems group. "Once a device is upgraded to Windows 10, we will be keeping it current for the supported lifetime of the device."
Microsoft did not clarify what "supported lifetime of the device" meant, however.
The Redmond, Wash. company's standard practice until now has been to support an OS for 10 years with security updates, but fix non-security bugs or add features, if any, only during the first five. Upgrades from one edition to the next -- from Windows XP to Windows 7, or Windows 7 to Windows 8 -- have always comes with a price tag, ranging from a low of $40 to a high of $200 for consumers and small businesses.
Windows 10's free upgrade -- even though for a limited time -- and Microsoft's promise to support it with free updates and upgrades for an extended period, is an enormous change for the company. It is also one that many analysts had not only seen coming but thought long overdue.
"They needed to move to this model, from a release every few years to one with constant upgrades," said Jan Dawson, chief analyst at Jackdaw Research.
Microsoft's free upgrade is essentially a consumer-only play, analysts said yesterday. Enterprises traditionally stick to their own, more conservative upgrade pace. Most corporations have annuity-like agreements -- Software Assurance -- that allow them to upgrade from one edition of Windows to another, and would be unlikely to push toward Windows 10 in the first year in any case. Gartner, for example, has said enterprises won't start deploying Windows 10 in numbers until 2018.
"For consumers it's a huge deal," said Michael Silver of Gartner in an email today. "For enterprises, it's only a big deal if they can manage the amount of change that goes with Windows 10."
And the experts agreed that the free deal would jumpstart Windows 10.
"The free upgrade is going to be huge," said Dawson.
"This should drive a big upgrade cycle," echoed Patrick Moorhead, principal analyst at Moor Insights & Strategy.
How big According to a Computerworld analysis last year, Microsoft should be able to get about 18% of all Windows personal computers onto Windows 10 within seven months of its release, which would be an uptake speed record for Microsoft.
Microsoft's move follows the lead set by mobile operating systems like Google's Android and Apple's iOS -- which provide free upgrades at least annually -- and that of Apple's OS X Mac operating system, which has been free since October 2013.
"The year [of the free upgrade deal] is a logical cut-line for Microsoft," said Wes Miller, an analyst with Directions on Microsoft. "It's not because businesses won't upgrade that quickly, but more Microsoft's way to compel [rapid upgrades]."
But it's not corporate generosity at work: There are solid business reasons for giving away Windows 10.
Myerson acknowledged that yesterday. "Today, Windows customers are spread across many versions," he said. "This fragmentation makes it challenging for developers to delight our customers with applications."
If Microsoft can entice hordes of consumers to upgrade to Windows 10, especially the huge numbers now running Windows 7, it will be able to build a bigger pool of potential customers for apps from third-party developers and services shilled by Microsoft. The lack of apps, caused in part by Windows 8's fiasco, has also branded Windows as an also-ran OS in a world where mobile is king, queen and court.
To give an idea of the potential for Windows 10 upgrades, one only needs to look at the current user shares owned by Windows 7 and Windows 8.1. Metrics firm Net Applications estimated the total user share eligible for the free upgrade at just over 76% of all Windows-powered PCs.
As is typical, Microsoft's plans were outlined in enough generality that they triggered additional questions.
For example, Myerson described Windows 10's constant update and upgrade process as "Windows as a service," and even boasted of its potential. "In the next couple of years, one could reasonably think of Windows as one of the largest Internet services on the planet," Myerson said.
That immediately prompted some to wonder whether Microsoft is headed toward a service-style subscription model for Windows. Not the case, analysts said.
"'Windows as a service' is about how it's a conduit to customers, about how Microsoft is delivering Windows 10, not the business model," said Miller.
Microsoft CEO Satya Nadella also weighed in during a Q&A session at the end of Wednesday's presentation, telling reporters, "There is no fundamental shift to our business model that we are announcing today," when asked whether Windows would morph into a subscription service similar to Office 365.
Other unanswered questions revolved around exactly what form the free Windows 10 upgrade will take, as in what version will be handed over sans charge. Microsoft has always built and sold a sometimes dizzying array of versions -- Windows 8.1 has three, ranging from the entry-level Windows 8.1 to the middling Windows 8.1 Pro to the corporate Windows 8.1 Enterprise -- and there's no reason to think that won't continue.
Microsoft hinted as much yesterday. In a footnote to a blog posted by Myerson on Wednesday, Microsoft plainly stated, "Some editions excluded," about the free upgrade deal.
The free upgrade may well be a less-capable version of Windows 10, analogous to Windows 8.1, that omits domain joining and other enterprise-grade features found only in the Enterprise and Pro versions. That would let it continue to charge customers who need those business tools, perhaps for a bump-up fee like Windows 7's Anytime Upgrade for ones and twos, or through agreements for larger volumes.
Customers can register an email address with Microsoft to receive more information about the upgrade offer and when it's available on the firm's website.