outlook keeps downloading emails and freezing

Question

Upon opening Outlook Classic. It downloads old emails, last time nearly 2000 emails totalling193 Mb. It freezes halfway and stops working. This occurs in safe mode to.

Any suggestions on how to fix this? Outlook has stopped working for me on my laptop.

Answer 1

Hi @Alex Lowery, 

Welcome to Microsoft Q&A forum. 

Thank you for reaching out and sharing your concern. I’m truly sorry to hear about the issue you’re experiencing with Classic Outlook. As a forum moderator, I genuinely wish I could directly access your account or delve into the backend systems to diagnose and fix this for you. However, our role here is limited to providing general guidance and solutions that can be applied by users.  

Based on my research, it appears you may be affected by a newly identified and significant known issue related to the Windows 11 Security Update KB5074109, released on January 13, 2026. 

Microsoft has officially confirmed that this update causes Outlook Classic to hang, freeze, or fail to restart because the application is not exiting properly in the background. This issue primarily impacts users with POP account profiles, but many Microsoft 365 users are reporting similar freezing. 

To resolve this issue, Microsoft has rolled out a follow-up fix through Windows Update, and there are a couple of steps you can try to restore normal Outlook functionality. 

Option 1: Update Windows  Ensure your system is fully up to date. Go to Settings > Windows Update, install all available updates (including optional and cumulative updates), and restart your device. After restarting, check whether Outlook Classic continues to hang, freeze, or fail to close properly. 

Option 2: Recreate your Outlook profile  If updating Windows does not resolve the issue, the Outlook profile may have been affected.  

1. Close Outlook completely and confirm it is not running in Task Manager.  
2. Press Windows + R key to open the run dialog box, type control, then press Enter to open the Control Panel. 
3. Click on Mail. 

4. Click on Show Profiles in the Mail Setup. 

5. Tap on the Add button to add a new file. Input the name and click OK. 

6. Click on Mail in the control panel and select the Data Files tab. 
7. Select the new Outlook profile from the list, then click the Set as Default option. 
8. Exit the Control Panel and restart tor PC, then check if the error persists. 

I hope this information is helpful. Please follow the steps above and let me know if it works for you. If not, we can continue working together to resolve the issue.  

Thank you for your patience and understanding. If you have any questions or need additional assistance, please don’t hesitate to reach out so I can continue to support you. If you found the response useful, please consider marking it as accepted, as this may help other community members who are looking for similar guidance.  

I look forward to continuing the conversation.   

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