Wi-Fi Sense is a feature built into Windows 10. You may see a pop-up saying “Wi-Fi Sense needs permission to use your Facebook account.” It also works with Outlook.com and Skype contacts.

This feature allows you to share Wi-Fi login information — network names and passphrases — with your friends. It’s designed to automatically connect Windows 10 devices to shared networks.

What is Wi-Fi Sense?

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Wi-Fi Sense was originally a Windows Phone 8.1 feature that made the jump to desktop PCs and tablets with Windows 10.

This feature lets you share Wi-Fi network access with your Facebook, Outlook.com, and Skype contacts. It works in the background, automatically sharing networks you choose to share and downloading credentials for Wi-Fi networks your contacts have shared with you.

When you visit your friend’s house or place of business, Windows 10 can automatically sign you into their Wi-Fi if they’ve shared it with you — that’s the idea.

Sharing Wi-Fi Networks With Your Contacts

You get to control which of your Wi-Fi network connection details are shared. When you connect to a Wi-Fi network in Windows 10, you’ll see a “Share network with my contacts” checkbox.

If you check this box, the connection details are automatically shared with your contacts using Windows 10 devices. The Wi-Fi Sense feature will detect when it’s near a shared network and automatically connect. If you want to give your friends easy access to your home Wi-Fi network, this will allow you to do it — assuming they use Windows 10 devices, of course.

Microsoft Wants to Know Who Your (Facebook) Friends Are

Like many other applications and services, Wi-Fi Sense can tap into your network of Facebook contacts. If you give it access to Facebook, it’ll share any shared networks with your Facebook friends and automatically download any networks your Facebook friends are sharing with you.

That’s the point of Wi-Fi Sense’s Facebook access — it allows Windows 10 to determine who your friends are so it can share Wi-Fi networks with them in the background. Technically, “Windows Wi-Fi” is a third-party app that accesses your Facebook friends so Microsoft knows who you’re friends with.

Microsoft doesn’t need to ask for access to your Skype and Outlook.com contacts because these other services are both owned by Microsoft and tied to your Microsoft account.

Configuring Wi-Fi Sense

Wi-Fi Sense settings can be controlled from the Settings app. Select Network & Internet, select Wi-Fi, scroll down, and select Manage Wi-Fi Settings.

From here, you can disable Wi-Fi sense entirely if you like, and choose whether Wi-Fi Sense automatically connects you to networks shared by your contacts — by default, it does. You can also choose which types of contacts Wi-Fi Sense shares connection details with — Outlook.com, Skype, and Facebook contacts are the only options here.

Scroll down and you’ll see which of your known networks you’ve shared, and which you haven’t. You can quickly choose to share a Wi-Fi network you’ve connected to in the past, or unshare a network you’ve previously chosen to share.

What If You Don’t Want Your Wi-Fi Connection Passphrase Shared?

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You might not want to use Wi-Fi Sense. Bear in mind that the sharing is indiscriminate — if you use it, it will share access to your Wi-Fi with all of your Facebook friends without letting you pick and choose who gets access.

If someone connects to your network with a Windows 10 device, they can choose to share the connection details with all their friends — at least those friends using Windows 10. You can choose to opt out of this by changing your wireless network name, or SSID, to end with _optout. In other words, if your network name is currently “HomeNetwork”, Microsoft would like you to change the name to “HomeNetwork_optout” to opt out.

Wi-Fi Sense is designed to automatically share Wi-Fi passphrases between friends, eliminating the need for handing them over the old-fashioned way and typing them in by hand. Whether or not you want to connect to Facebook and share Wi-Fi connections amongst your friends is up to you. If you don’t want your friends sharing your Wi-Fi network, you’ll have to label it with “_optout”.