But Microsoft's aggressive promotion of Windows 10, including a free upgrade to most consumers running Windows 7 or Windows 8.1, was meant to dramatically boost 10's uptake compared to previous upgrades, including the benchmark Windows 7.
That hasn't happened.
The continued slowdown, as well as Microsoft's self-set goal of putting Windows 10 on a billion devices by mid-2018, was probably a factor in the Redmond, Wash. company's announcement two months ago to automatically serve the Windows 10 upgrade to most consumer and small business Windows 7 and Windows 8.1 PCs in early 2016.
While Microsoft outlined the plan in late October and at the time said the two-part scheme would kick off "soon" by adding the Windows 10 upgrade as an optional item to Windows Update -- the precursor to listing the upgrade as an automatic download -- that first step has not yet occurred.
Windows 10's user share nearly reached 11% by the end of 2015, but gains continued to shrink, and for the first time fell behind the pace set by Windows 7 in 2009-2010. Click on image to enlarge. Data: Net Applications
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