I can't use outlook

A current Microsoft 365 service issue is affecting Outlook access for some users, so use Outlook on the web temporarily and have your Microsoft 365 administrator check Health > Service health before repairing or reinstalling New Outlook. ^1^

Access your inbox now

1. Open a browser and go to Microsoft365.com.
2. Sign in with your work or school account and complete any multifactor-authentication prompt.
3. Open the app launcher and select Outlook. ^2^

The result determines the next action:

• Web Outlook works: Your mailbox remains accessible; continue using the browser while the service incident is investigated. If other colleagues have the same problem, avoid resetting or reinstalling the application until service health reports recovery.
• Web Outlook also says “Access denied”: Contact your organization’s IT administrator. This points beyond the local Windows application and requires the administrator to check the service incident and your account/mailbox access.

Administrator check

A Microsoft 365 administrator, Service Support administrator, or Helpdesk administrator should:

1. Sign in to the Microsoft 365 admin center.
2. Go to Health > Service health.
3. Open any active Exchange Online or Outlook incident and review its status and workaround.
4. Also check Issues for your organization to act on.

The dashboard distinguishes incidents Microsoft is already resolving from tenant-specific issues that require administrator action. ^3^

If web Outlook works and service health is normal

Treat this as a local New Outlook problem:

1. Right-click Start and select Task Manager.
2. Select Microsoft Outlook, then End task.
3. Reopen New Outlook.

If the access-denied message remains:

1. Open Start > Settings > Apps > Installed apps.
2. Find Outlook (new) and select More (…) > Advanced options.
3. Select Repair, then reopen Outlook.
4. If Repair does not help, return to the same page and select Reset.

Resetting removes the app’s local data and may require you to sign in and add accounts again. Windows documents Repair first and Reset only if Repair is unavailable or unsuccessful. ^4^

If Reset also fails, uninstall new Outlook for Windows from Start, restart Windows, and reinstall it from Microsoft Store. Microsoft requires Windows 10 version 17763.0 or later for that installation. ^5^

Do not use classic Outlook’s /safe, profile, or scanpst.exe procedures for this case unless the New Outlook toggle is off; Microsoft states that classic Outlook troubleshooters do not apply to New Outlook for Windows. ^6^

References

1. Microsoft 365 Status (@MSFT365Status) / X
2. How to sign in to Outlook on the web | Microsoft Support
3. How to check Microsoft 365 service health
4. [Windows 11](https://support.microsoft.com/windows/apps/repair-apps-and-programs-in-windows#summary)
5. Outlook for Windows not responding, hangs, freezes, or stops working | Microsoft Support
6. Resolve Outlook for Windows issues with automated troubleshooting tools | Microsoft Support