Got an email signed Microsoft, One Microsoft Way Redmond. Scam?

The address doesn't tell you anything either way. It's Microsoft's real headquarters and it's in the footer of their genuine emails, which is exactly why scammers paste it into fake ones. What does tell you: check the actual sender address (tap the name to see it, not just the display name), and look at what it wants. A phone number to call, a payment, an urgent "your account will be closed" or a link to sign in are the usual signs. Safest thing is to ignore the email entirely. Open your browser, go to your Microsoft account yourself and check recent activity and any notices there. If it was real, the same alert will be waiting.