When will Microsoft Exchange return online.? Email service stopped at 12PM and is still out at 8:41PM.

Check Microsoft 365 admin center → Health → Service health → Exchange Online for the current restoration estimate and incident updates; Microsoft does not provide one universal recovery time because impact and recovery can differ by tenant and region.^1^

If you use Microsoft 365 / Exchange Online

1. Sign in to the Microsoft 365 admin center with an administrator account.
2. Open Health → Service health.
3. Select the active Exchange Online incident or advisory.
4. Review:
   • Status
   • User impact
   • Last updated
   • All updates, including any estimated recovery time

Current public indications point to an Exchange Online/Microsoft 365 disruption, but the Service Health dashboard is authoritative for whether your organization is affected.^2^

If Exchange Online is listed as degraded or interrupted, Microsoft is already restoring the service. There is normally no tenant-side action that can bring it online sooner; continue monitoring the incident. Microsoft uses statuses such as Investigating, Restoring service, Extended recovery, and Service restored to show progress.^1^

If the admin center itself is inaccessible, check the public Microsoft service-status page linked from Microsoft’s service-health documentation.^1^

If no Exchange Online incident appears

An administrator should:

1. On Health → Service health, select Report an issue.
2. Run Diag: Troubleshoot Email Delivery in the Microsoft 365 admin center.
3. Open Exchange admin center → Mail flow → Message trace.
4. Search from shortly before 12 PM through the present, specifying an affected sender and recipient.
5. Open a result and review Status, Details, and How to fix it.

Message trace identifies whether messages were delivered, blocked, delayed, or never reached Exchange Online. Trace data can take from about 10 minutes to one hour to appear.^3^

If diagnostics do not identify the problem, open a Microsoft 365 support request and include:

• Outage start time and time zone
• Number of affected users
• Whether sending, receiving, sign-in, or all functions fail
• Example sender and recipient addresses
• Message timestamps and any non-delivery report codes
• Message-trace results

If this is an on-premises Exchange Server

The Microsoft 365 incident does not restore a locally hosted Exchange server. If mail flow stopped immediately after installing a cumulative or security update, verify that:

• All Exchange services are running and configured to start automatically.
• The server is not left in maintenance mode.
• The drive hosting the Exchange message queue database has sufficient free space.^4^

If Exchange Server 2013 or 2016 logs Event ID 7009 or reports that the server is inactive, check the Hub Transport component. Only under that specific condition, reactivate it from the Exchange Management Shell and restart the Exchange Transport service:^5^

Set-ServerComponentState `
  -Identity "<ExchangeServerName>" `
  -Requester Functional `
  -State Active `
  -Component HubTransport

Restart-Service MSExchangeTransport

Do not run this Exchange Server command against Exchange Online or unless the component is confirmed inactive.

References

1. How to check Microsoft 365 service health
2. EXCHANGE IS DOWN - Microsoft Q&A
3. Find and fix email delivery issues as a Microsoft 365 for business admin
4. Fix failed Exchange Server updates
5. Event 7009 when users try to send or receive email in Exchange Server 2013 or Exchange Server 2016