More than a dozen Microsoft products and services are no longer able to integrate with Facebook directly.

As Windows Central first reported, a number of Microsoft offerings that relied on integration between users' Microsoft and Facebook accounts will no longer work as they have to date.Among the affected products are Outlook.com Contacts, Calendar sync, Windows 8.x People and Calendar apps, OneDrive Online, Office 365 Outlook Web app and more.

In an article on the Microsoft Office support site, entitled "Facebook Connect is no longer available," Microsoft attributes the discontinuation of support to a change Facebook has made to its Graph application programming interface (API).

From that article:

Microsoft has posted a support article offering some suggested workarounds for various services that have relied on Facebook Connect integration.

Facebook announced way back in 2010 that it planned to drop Facebook Connect and replace it with the Open Graph protocol. The Facebook developer page for Facebook Connect has been removed, though I'm not sure exactly when that happened.

Update (June 10): A Facebook spokesperson said that the Facebook Connect API which I referred to above was not succeeded by the Graph API.

Here's Facebook's clarification:

"This change is actually not related to that (above-mentioned Facebook Connect) product, which eventually became Facebook Login. It's related to an update to our Graph API that we announced in 2014, and which affected the suite of API connections that Microsoft collectively refers to as 'Facebook Connect.' "As one of the changes that we made to our API, we announced that people can now only share their own information with apps; they can no longer share their friends' information (e.g. Likes, photos, birthday, etc.) We made this change because we heard feedback that people were surprised when their friends shared their information with an app. The new Graph API gives people more control over how their own information is shared with apps."

These changes apply to all developers who build apps connected to Facebook, the spokesperson emphasized.

"We gave developers one year to make the changes in their apps and upgrade to the new API. Now, the changes we made to Login and our APIs have fully come into effect and all developers are required to use the new API," the spokesperson noted.