Users of those operating systems have been allowed to "reserve" an upgrade since June. Microsoft then pre-loads the Windows 10 upgrade bits -- as much as 6GB worth -- to those devices, but staggers the notifications displayed on customers' computers to alleviate server overload.
Windows 10's usage share remains higher than Windows 7's at the same post-release point, but the gap has been shrinking, largely because Windows 7 launched later on the calendar -- October rather than July -- and thus accumulated impressive gains around the 2009 holidays as large numbers of consumers and some businesses bought new PCs near year's end.
Windows 10 should crack the 10% usage share mark for the first time on Sunday, reinforcing the impression that the free upgrade gave the OS about a one-month boost compared to Windows 7, which was a paid upgrade and also obtained through device purchases.
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