Xbox Live has stopped working, leaving gamers unable to play.
Outages on the console's online service are especially dramatic because they leave players unable even to sign in and play games.
The problems come as more players than usual are at home practising social distancing to avoid spreading coronavirus, and so the outage probably hit even more players than usual.
Microsoft's Xbox Live status page appeared to be affected by the outage, leaving players unable to even check whether the service was down.
But the company confirmed the problems in a tweet and tens of thousands of people complained that they had been left unable to get onto the service.
"We understand some users may be experiencing errors with sign in or matching making on Xbox Live, and are currently investigating," the official Xbox support page posted.
Outage tracking website Down Detector showed a vast number of issues.
Most of the issues were seen in the UK and US, though that might simply be a consequence of timezones meaning that players from those area are most likely to be online.
Problems began around 9pm UK time, according to Down Detector.
