One anecdote I have about Microsoft is that I once set up in Hotmail my birthday 5 months in advance to what it was, probably to bypass some 18yo check. Eventually (5 months later, probably) I set it back to normal.
Since then, for a couple of years, my father got a notification saying that it was my birthday (and he even obliged to congratulate me, once; he was -- and luckily is -- old :) ). That setting was not available anymore anywhere, and my birthday was set to the correct date, but the problem still happened. I contacted Microsoft, but it was like they had no idea what I was talking about nor what could be the problem.
Since then, for a couple of years, my father got a notification saying that it was my birthday (and he even obliged to congratulate me, once; he was -- and luckily is -- old :) ). That setting was not available anymore anywhere, and my birthday was set to the correct date, but the problem still happened. I contacted Microsoft, but it was like they had no idea what I was talking about nor what could be the problem.
So yeah, I don't trust them nor like them either.