Using classic Outlook for Windows in business environments
The repair time cannot be confirmed publicly; your Microsoft 365 administrator should check Admin center → Health → Service health → Exchange Online/Outlook for the incident status, latest update, and any restoration estimate.
Check the current incident
- Sign in to the Microsoft 365 admin center with an admin account.
- Open Health → Service health.
- Under Active issues Microsoft is working on, look for Exchange Online or Outlook.
- Open the incident to view:
- User impact
- Current status
- Last update
- Microsoft’s mitigation progress and restoration estimate, if provided
Microsoft posts updates there while investigating and restoring service. If the admin center itself is inaccessible, use Microsoft’s public service-status page referenced in the same documentation. Service Support Admin and Helpdesk Admin roles can also view service health.^1^
If you are not an administrator, ask your organization’s IT team to check the incident for your tenant. A precise completion time should not be assumed unless it appears in that incident’s updates.
Determine whether it is local
Try signing in through Outlook on the web:
- Web and desktop both fail, especially for multiple employees: treat it as a possible Microsoft 365 or organizational account incident and follow Service health.
- Web works but classic Outlook fails only on this PC: run the authentication troubleshooter:
- Close Outlook.
- Open the Windows Get Help app.
- Search for Outlook password problem.
- Run the suggested checks and reopen Outlook.
For intermittent connection failures, use the classic Outlook connectivity troubleshooter instead. These tools require Windows 10 or later, must run on the affected PC, and do not apply to new Outlook for Windows.^2^
Microsoft also maintains a current list of fixes and workarounds for known classic Outlook issues.^3^
If no incident is listed but several users are affected, an administrator can select Report an issue on the Service health page. If only one account fails, provide IT with the exact error message, whether Outlook on the web works, and the Get Help results.
References