Check the Service health dashboard to make sure that there isn't a service outage affecting your organization. If there's ...

Check the Service health dashboard to make sure that there isn't a service outage affecting your organization. If there's an issue listed for Exchange Online, we're already working on the problem. You don't need to open a service request. The service health dashboard provides you with the most up-to-date information about when the problem will be fixed.

If there isn't a service outage, please continue creating a service request. We'll need to investigate this problem further to solve it.