Windows 10 Wi-Fi Sense feature shares your Wi-Fi network with your friends

And here's another bad idea.  Underlined text is to highlight security issues.

From Sophos Naked Security:

Windows 10 Wi-Fi Sense feature shares your Wi-Fi network with your friends

Have you ever been to a friend's house and wanted to connect your phone or tablet to their network to avoid using your mobile data allowance? If so, you know it can be a minor inconvenience having to ask for the Wi-Fi password, and then to tap it via the on-screen keyboard.

Microsoft has come up with a solution for that. Wi-Fi Sense is a feature of the soon-to-be-released Windows 10 operating system that not only allows you to automatically connect a compatible device to any in-range open crowdsourced Wi-Fi network, but also grants access to password-protected networks by sharing login credentials between friends.

The feature, which can automatically accept a Wi-Fi network's terms and conditions and provide your name, email address or phone number on your behalf, also allows you to share access to password-protected Wi-Fi networks with Outlook.com and Skype contacts, as well as Facebook friends (via an opt-in), all on a per-service rather than per-person basis.

While Wi-Fi Sense doesn't explicitly hand over your passwords to your friends, it does need to store them centrally in order to present them to the Wi-Fi Sense connection software on your buddies' devices as and when required.

From Microsoft's FAQs page:

For networks you choose to share access to, the password is sent over an encrypted connection and stored in an encrypted file on a Microsoft server, and then sent over a secure connection to your contacts' phone if they use Wi-Fi Sense and they're in range of the Wi-Fi network you shared. Your contacts don't get to see your password, and you don't get to see theirs.

How secure that element of Wi-Fi Sense is, we don't yet know.

But what we do know is that access to your network can, depending on your choices, be shared between all your contacts on Outlook.com, Skype and/or Facebook. So, you could be inadvertently granting access network to people you don't know all that well.