Caveats abounded in Gartner's prognostication, however. "What we could see happen is that [enterprises] see the process as smoother than they now believe will be the case," said Kleynhans. Or migrations could hit hitches, and lag behind his cadence conjecture.
One factor that plays to faster, not slower, upgrade schedules is that for many companies, this is déjà vu all over again.
"A big thing is there is some pent-up demand for devices like the Surface Pro 4, that class of 2-in-1 and convertible devices," said Kleynhans, referring to the small-but-quickly-growing category of hardware with detachable or pivot-style screens. Corporations tried, but failed, to support those devices with Windows 8, and a year later, Windows 8.1, Kleynhans observed.
"IT made promises to users a year ago, but failed to deliver," he said. "Now they're trying to reinstate those projects with Windows 10."
Others besides Gartner have scrambled onto the fast Windows 10 adoption bandwagon. Adaptiva -- a Bellevue, Wash. company that specializes in systems management, specifically for Microsoft's System Center Configuration Manager (SCCM) -- recently publicized a survey of IT professionals that showed 12% of the respondents' companies had installed Windows 10 on 5% or more of their PCs.
Forty percent of those companies -- thus representing about 5% of the total -- said that Windows 10 was on half or more of their systems. And 60% of the firms what now have 5% or more of their machines running Windows 10 -- or just over 7% of the total -- claimed that they would have half or more of their PCs on the new OS within the next year.
Adaptiva characterized enterprise interest in Windows 10 as "unprecedented adoption of the new operating system." But the small fraction of those that have broken the 5% barrier with pilots actually illustrates that, while interest in Windows 10 may well be significant, the bulk of corporations will almost certainly conduct large-scale deployments on Gartner's timeline, meaning in 2017 and 2018.
It's no coincidence that businesses will shoot for that schedule: All Windows 7 support ends in January 2020, and under a new scheme Microsoft just revealed, support for the older OS on newer hardware will come to a halt in July 2017.
"Part of the interest in Windows 10 is that enterprises are very aware of the end-of-life of Windows 7," said Kleynhans.
As they should be: Many companies learned the hard way when, as Windows XP's support wound down in the spring of 2014, they had to scramble to purge the ancient operating system. "They want to avoid those issues," Kleynhans said.
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