Update 5:44pm PT: Xbox Support says the sign in alert is no longer present, meaning logging into Xbox Live accounts shouldn’t be a problem now.
You can keep up to speed with all Xbox Live issues over on its status page as well as with the Xbox Support Twitter account. The latter encourages users to shoot over any questions if they are still experiencing problems or have concerns.
The sign in alert has been cleared! If you tweeted earlier and still have a question, please let us know and we’ll respond ASAP.March 22, 2017
Original story below…
Xbox Live is currently experiencing issues, with users unable to log into the Microsoft-branded gaming network for not just the Xbox One, but also Xbox 360 consoles and Windows 10 PCs.
This issue stems hours after users had reported difficulties accessing purchased digital content on their machines, which is also being addressed by Microsoft’s Xbox Support team.
We’re aware of reports of trouble logging into Xbox Live. We’re working hard to get things resolved. Stay tuned to: https://t.co/99xfLMWcZWMarch 21, 2017
The Xbox Support team is currently working on a fix, though no detailed information explaining the source of the error or how long players can expect to stay locked out were given.
We’ve contacted Xbox to learn more about the extent of the problem, though eager users can also keep an eye on Xbox Live’s status page for continual updates on the service.