Loading Outlook

Question

When I click on the New Outlook icon it fails to load or loads and immediately closes. If I click on Outlook Classic it most often loads (but not all the time) and then swaps to the New Outlook. What is going on? How to fix?

Answer 1

Hi @Jonathan Carter-Meggs,

Thank you for posting your question in the Microsoft Q&A forum.

I can understand how inconvenience it can be when Outlook won’t open and you need it for work. When you launch Classic Outlook but it switches to New Outlook, this happens because Microsoft began an automatic switch rollout last year. The good news is that you can still switch back if needed. You can find more details here: Switch to new Outlook for Windows.

To help resolve the issue, here are a few steps you can try, starting from the simplest:

1/ Make sure Outlook isn’t stuck in the background:

Press Ctrl + Shift + Esc to open Task Manager and end any Microsoft Outlook / Outlook (New) / Calendar / OneAuth processes. Then, try launching Outlook again. For more guidance, Microsoft’s troubleshooting page begins here: Troubleshoot Outlook for Windows issues.

2/ Repair or reset the “Outlook (New)” app:

• Go to Settings > Apps > Installed apps > Outlook > Advanced options, then select Repair. If it still won’t open, choose Reset (this clears local cache, so you’ll need to sign in again).
  

3/ Rebuild local Outlook cache that commonly blocks startup:

• Close Outlook. In File Explorer, paste and delete or rename these folders (they’ll be rebuilt automatically):

%localappdata%\Microsoft\Olk

%localappdata%\Microsoft\OneAuth

Then restart Windows and open Outlook again.

4/ Repair or reinstall Microsoft Edge WebView2 runtime:

• The new Outlook relies on WebView2 to render its interface. If WebView2 is missing or corrupted, Outlook may not open.
• Download the Evergreen Standalone WebView2 installer from Microsoft and Run as administrator, then launch Outlook.

You can follow the instructions here: New Outlook refuses to open.

5/ Fix broken sign‑in components (WAM/AAD Broker Plugin):

If you see a blank sign-in pane or Outlook never authenticates, the Web Account Manager plug-ins may be broken. Microsoft explains the symptoms and fixes here.

6/ Run SaRA (Support and Recovery Assistant):

• Download and run the Microsoft Support and Recovery Assistant to automatically diagnose and fix Outlook launch or authentication issues.
• You can download it here.

I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.   

Thank you for your patience and your understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you.

I look forward to continuing the conversation.

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Answer 2

When the New Outlook fails to load or closes immediately, it could be due to several reasons. Here are some potential causes and solutions:

1. Installation Issues: There may be installation issues related to security settings that prevent the New Outlook from launching properly. You can refer to the troubleshooting documentation for installation issues to resolve this.
2. Corrupted Profile or Data Files: If Outlook Classic is loading but then switches to New Outlook, it might indicate that there are issues with your user profile or the data files. Creating a new Outlook profile may help resolve this issue. To do this, go to Control Panel > Mail > Show Profiles, and then add a new profile.
3. Running Diagnostics: You can run the Classic Outlook Advanced Diagnostics troubleshooter to identify and fix issues that may be causing Outlook to crash or stop responding. This tool can help check for problems automatically.
4. Repairing Outlook: If the above steps do not work, consider repairing your Microsoft 365 programs. This can fix any corrupted files that might be causing the issue.
5. Check for Updates: Ensure that you have the latest updates installed for Outlook, as outdated software can also lead to performance issues.

If the problem persists after trying these solutions, you may want to reach out to Microsoft Support for further assistance.

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References:

• Resolve deployment issues in the new Outlook for Windows
• How to troubleshoot issues that cause Outlook to crash or stop responding when used with Microsoft 365