The Electronic Frontier Foundation has accused Microsoft of disregarding user choice and privacy with Windows 10. In a scathing editorial, EFF employee Amul Kalia calls on Microsoft to "come clean with its user community" over a growing number of Windows 10 privacy concerns. "Windows 10 sends an unprecedented amount of usage data back to Microsoft," explains Kalia, noting that enabling Cortana increases the amount of data passed to Microsoft. Privacy advocates have argued that Windows 10 sends back location, text input, voice input, touch input, websites you visit, and other telemetry data to Microsoft.

"While users can disable some of these settings, it is not a guarantee that your computer will stop talking to Microsoft's servers," says Kalia. "A significant issue is the telemetry data the company receives." Microsoft has previously insisted it anonymizes telemetry data, but the EFF is concerned the company hasn't explained exactly how it does this. "Microsoft also won't say how long this data is retained, instead providing only general timeframes."

While telemetry data is clearly a concern, the EFF focuses on Microsoft's confusing link between this data and security patches. "Microsoft has tried to explain this lack of choice by saying that Windows Update won't function properly on copies of the operating system with telemetry reporting turned to its lowest level," claims Kalia. "Microsoft is claiming that giving ordinary users more privacy by letting them turn telemetry reporting down to its lowest level would risk their security since they would no longer get security updates."

The EFF also blasts Microsoft for its aggressive Windows 10 upgrade tactics, although the company has recently ceased offering a free upgrade to Windows 7 and Windows 8.1 users. "The tactics Microsoft employed to get users of earlier versions of Windows to upgrade to Windows 10 went from annoying to downright malicious," says Kalia. Microsoft's upgrade prompts triggered a backlash after the company tweaked its notification to schedule Windows 10 upgrades even if someone dismissed the prompt. Microsoft agreed to pay one woman $10,000 over an automatic Windows 10 installation, and tweaked its upgrade notification as a result.

Microsoft's Windows 10 privacy headache has been growing over the past year, with some genuine concerns mixed with unnecessary fear. It's clear Microsoft has a trust issue with Windows 10 for those who do not wish to transmit data back to the software giant, no matter how anonymized it is. Microsoft was forced to address some of the concerns last year, but a lack of full transparency has forced the EFF to demand "real, meaningful opt-outs to the users who want them." Microsoft responded to the EFF concerns in a statement to ZDNet. "Microsoft is committed to customer privacy and ensuring that customers have the information and tools they need to make informed decisions," says a Microsoft spokesperson. "We listened to feedback from our customers and evolved our approach to the upgrade process. Windows 10 continues to have the highest satisfaction of any version of Windows."

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