Since July 29, Microsoft has been rolling out Windows 10 in waves to PCs around the world. So far, over 110 million devices are running the OS, which the company has made available as a free upgrade to those with Windows 7 and 8.1 PCs.
However, that free upgrade offer is optional, and while Microsoft has certainly done its bit to encourage users to upgrade, the decision to do so is ultimately left to them, and they must opt in to install the new OS on their devices - or so the theory goes. In fact, an error on Microsoft's part has automatically pushed the upgrade through to an unknown number of users.
Multiple users have so far reported that not only is the Windows 10 upgrade being downloaded to their systems, but the installation process actually launches and begins. Ars Technica's Peter Bright witnessed the scenario playing out for himself, observing that the 'Upgrade to Windows 10' optional update in Windows Update had been checked by default - and unless a user specifically viewed the Optional Updates tab before clicking 'OK', they wouldn't realize that they'd inadvertently given the thumbs-up to proceed with the upgrade.
There are further steps involved with installing the OS, though - so users will have had the opportunity to cancel the upgrade before it went ahead. But some less savvy users may well have gone ahead with upgrading to Windows 10, believing they had no choice.
All of this was the result of an unfortunate error on Microsoft's part, as a statement from the company explained:
As part of our effort to bring Windows 10 to existing genuine Windows 7 and Windows 8.1 customers, the Windows 10 upgrade may appear as an optional update in the Windows Update (WU) control panel. This is an intuitive and trusted place people go to find Recommended and Optional updates to Windows. In the recent Windows update, this option was checked as default; this was a mistake and we are removing the check.
You should now find that the Windows 10 upgrade option is unchecked on Windows Update - although there's always the chance that it will take a few hours for everything to return to normal. But do keep an eye on Windows Update - if you still see that checkbox being pre-ticked in the days ahead, be sure to let us know.
Source: Ars Technica