Windows 10's host of new features are matters mostly of convenience. Cortana can surface upcoming calendar events and keep you abreast of hometown sports, for instance. Microsoft Edge ostensibly makes browsing the web faster and easier. But some of those conveniences come at costs that aren't made clear, and Wi-Fi Sense is perhaps the most egregious: the feature, which is enabled by default in Windows 10, shares the network passcodes saved on your computer indiscriminately with your Outlook, Skype, and Facebook contacts.
The intention behind Wi-Fi Sense is good -- a shared database of Wi-Fi passwords that makes it easier to jump on friends' hotspots -- but the vagueness around it isn't. An FAQ explains that passwords are "sent over an encrypted connection and stored in an encrypted file on a […] server," but doesn't divulge the strength of the encryption, the method of transfer, and how long they're stored. That poses a problem not only for privacy -- some users would no doubt be uncomfortable granting Microsoft access to their wireless passwords -- but also security. Wi-Fi Sense data, from the sound of it, is an attractive hacking target.
To be fair, those concerns are a tad overblown. Wi-Fi Sense is only switched on if you choose the "Express" setup in new installations of Windows 10, and not during upgrades from Windows 7 or 8. And there's no indication that Wi-Fi Sense data is especially vulnerable to hackers. Indeed, Microsoft considers Wi-Fi Sense a more secure alternative to handing over the keys to your wireless kingdom, so to speak -- contacts automatically connect without seeing passwords and "[don't] have access to other computers, devices, or files stored" on networks, according to the FAQ.
Furthermore, passwords aren't shared with your contacts' contacts ("If your contacts want to share one of your networks with their contacts, they'd need to know your actual password and type it in to share the network," says the FAQ), and Wi-Fi Sense has shipped on Windows Phone since last year without user revolt or any database breaches. But it isn't customizable -- you can't exclude certain Skype or Outlook contacts from sharing -- or particularly transparent about how your wireless passwords are being stored and shared. Until that changes, leaving Wi-Fi Sense disabled might be worth sacrificing a little convenience.
Not sure how to disable Wi-Fi Sense in Windows 10? Open Settings, navigate to the Network submenu, click on "Manage Wi-Fi," and toggle off the relevant setting.