Oulook Classic Frozen Again

Dear Gail Martin,

Thank you for posting to the Microsoft Q&A.

I understand how frustrating it is to have your workflow disrupted a second time, especially after you had already successfully regained access by rolling back the previous update. What likely happened overnight is that Windows performed an automatic update cycle. If your "Pause Updates" period expired, the system may have re-applied the problematic configuration. However, we now have a permanent solution that replaces the need for uninstalls.

To provide the most accurate solution, could you please confirm which version of Windows you are currently using? If you see KB5074109 listed in your update history again, it confirms why the freezing has returned.

The good news is that the engineering team released a permanent fix for this behavior on January 24, 2026. This new update, KB5078127, is designed to resolve the freezing and sync issues once and for all.

Please follow these steps to install the patch:

1. Open Windows Settings.
2. Go to Windows Update.
3. Click Check for updates.
4. Ensure you download and install Security Update KB5078127.
5. Restart your computer once the installation is complete.

Updating to this version should resolve the sync issues and prevent Outlook from hanging during startup. If you continue to see prompts after checking these settings, please do not hesitate to let me know.

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