You probably need good lighting conditions for the SP4 to see your image. It's not like a magic camera that can log you in a room with no lights on.
Wait, so for the facial recognition to work, you need internet access? How come it wasn't seeing your face?
Oh it was seeing my face, it would just constantly tell me that I wasn't connected to the internet and therefore I needed to sign in using an alternate way. So I guess since I have a Microsoft Account it's tied to that and in turn is in some way tied to internet access.
It was a pretty aggravating loop of not being able to do anything. Taking the Type Cover off finally got me to be able to use my password to login, but even that was painful. So it's turned off for now.
You probably need good lighting conditions for the SP4 to see your image. It's not like a magic camera that can log you in a room with no lights on.
I have the RealSense camera mounted on a PC and because it uses infrared, room lighting can be nil and it still does facial recognition perfectly.