I've never been able to log into my Xbox account on one of my PCs. To this day, it insists I need to have Xbox Gaming Services installed when I already do and have re-installed them multiple times. Devs have yet to acknowledge that anyone is facing this issue, to my knowledge. When they updated to introduce a "path" for users to sign into Xbox, all they did was add a pop-up telling people to install Gaming Services when they already have. Sucks, big time.