"The new policies take effect on 1 August and there are a few unsettling things nestling in there that you should be thinking about if you’re using the company’s services and software.
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Sign into Windows with your Microsoft account and the operating system immediately syncs settings and data to the company’s servers. That includes your browser history, favorites and the websites you currently have open as well as saved app, website and mobile hotspot passwords and Wi-Fi network names and passwords.
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Turn on Cortana, the virtual assistant, and you’re also turning on a whole host of data sharing: [...] "your device location, data from your calendar, the apps you use, data from your emails and text messages, who you call, your contacts and how often you interact with them on your device. [...] your music, alarm settings, whether the lock screen is on, what you view and purchase, your browse and Bing search history, and more.”
Lots of things can live in those two words “and more.” Also note that because Cortana analyzes speech data, Microsoft collects “your voice input, as well as your name and nickname, your recent calendar events and the names of people in your appointments, and information about your contacts including names and nicknames.”
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The updated terms also state that Microsoft will collect information “from you and your devices, including for example ‘app use data for apps that run on Windows’ and ‘data about the networks you connect to.'”
Windows 10 generates a unique advertising ID for each user on each device. That can be used by developers and ad networks to profile you.
[...] When device encryption is turned on, Windows 10 automatically encrypts the drive its installed on and generates a BitLocker recovery key. That’s backed up to your OneDrive account.