Microsoft's Xbox One is currently unusable as server issues leave the devices with black screens. But don't worry, it's not broke. It's just an issue with Xbox Live.
Many people are reporting seeing a black screen shortly after their console boots up. Microsoft has tweeted that it’s aware of the “Xbox One console startup, title update, and sign-in errors” and will provide updates as it can. It’s pointing people to the system status page, but that’s also down at the moment.
One fix might be unplugging the Ethernet which allows the console to start up normally since it’s not making a connection to Live. But if your console is connected via Wi-Fi, a workaround might be more challenging until Microsoft fixes this.
XboxSupport believes they have determined the service causing the issues and they are working to roll back the service and resolve the situation. The time frame for the fix is still unknown.