I'm at a college where we have a campus licensing agreement with Microsoft for licensing Windows and Office that now includes Office 365 online services, which includes Skype for Business. I'm playing with Skype, and it's a decent IM and presence app on it's own. The screen sharing features are nice.
The trick here is that we don't have Exchange anywhere (we have G Suite Apps for Edu handling our e-mail services). I've come across a few places in the Skype program that complain about this:
The thing is... I am able to sign in and exchange messages with another user. Accounts are synced from Active Directory to Azure AD, and authentication happens via AD FS.
We have no plans or desire to add Exchange here. However, I have a hard time recommending anyone use the software if it's going to have so many "errors" right on the surface. It looks like it's my fault, that I've missed something, and will create lots of service calls. Can I make these errors go away? Have I just missed something in the setup?
Part of the Office 365 experience is when you buy the suites they are meant to be integrated and work together with very little if any input from admins or users.
Skype for Business shares some things with Outlook and looks for Exchange for certain functions.