I noticed this as well. I got three 950's from AT&T. While setting them up, my wife's phone had issues. She logged in to her outlook account at setup, however post-setup the account was gone. Attempting to use the store or anything else said to log in, however when you would go to log in it said you would need to check the store for an app to perform that feature.
I tried to use the device recovery to reset it and found nothing available. I ended up doing the hardware key recovery to reset the device to factory and start over. It worked fine after that.