Outlook email

Your Microsoft 365 administrator should check Microsoft 365 admin center → Health → Service health → Exchange Online, because any available restoration estimate and Microsoft’s latest recovery updates are published there for your organization.^1^

Check the restoration status

1. Sign in to the Microsoft 365 admin center with an administrator, Service Support administrator, or Helpdesk administrator account.
2. Select Health → Service health.
3. Under Active issues Microsoft is working on, open the Exchange Online or Outlook incident.
4. Review:
   • Status
   • User impact
   • Last updated
   • All updates, where Microsoft posts investigation and restoration progress

An exact recovery time cannot be determined outside your tenant’s incident record. If the status is Restoring service or Extended recovery, remediation is underway, but recovery may reach affected systems gradually. When Exchange Online is shown as degraded, Microsoft engineers are already working on the incident; continue monitoring that record rather than changing Outlook profiles or devices.^2^

To receive updates automatically, go to Service health → Customize → Email, enable service-health notifications, and select the relevant services. Notifications can be sent to up to two addresses per administrator.^1^

If the admin center is unavailable

Use Microsoft’s public service status page. It is intended for checking known issues when administrators cannot access the tenant-specific Service health dashboard.^1^

If no Exchange Online incident appears

Select Report an issue on the Service health page. Microsoft correlates the report with data from other organizations and creates an incident or advisory if it identifies a service-side problem.^1^

As a quick isolation test, open the affected mailbox in Outlook on the web:

• If email works on the web but not in Classic Outlook, the problem is likely limited to the desktop client or computer.
• If multiple employees cannot send or receive through both Outlook on the web and Classic Outlook, have the administrator investigate Exchange Online service health and mail flow rather than treating it as an individual Outlook profile issue.^2^

References

1. How to check Microsoft 365 service health
2. Find and fix email delivery issues as a Microsoft 365 for business admin