Quick Summary
Microsoft has shared a temporary workaround for Outlook freezes affecting users with POP email accounts after the KB5074109 security update on Windows 11. The issue also impacts Windows 10 and various Windows Server platforms, causing Outlook to hang and emails to be redownloaded. Users are advised to access email via webmail or relocate PST files from OneDrive until a permanent fix is available.
The Securityish Brief
Microsoft has acknowledged an issue causing the classic Outlook desktop client to freeze for users with POP email accounts following the installation of the KB5074109 security update on Windows 11 versions 25H2 and 24H2. Symptoms include the inability to reopen Outlook without terminating the process via Task Manager, redownloading emails, and sent emails not appearing in the Sent Items folder.
This problem also affects Windows 10 users and multiple Windows Server platforms, including Windows Server 2025, Windows Server 2022, and Windows Server 2019. Microsoft has indicated that any app may become unresponsive when interacting with cloud-backed storage solutions like OneDrive or Dropbox, particularly if PST files are stored there.
While Microsoft is investigating the issue, no timeline for a fix has been provided. In the meantime, affected users can access their email accounts via webmail or move their Outlook PST files out of OneDrive to mitigate the problem. Alternatively, users can uninstall the KB5074109 or KB5073724 updates, although this poses a security risk as these updates address vulnerabilities that could be exploited by malware.
Recently, Microsoft released emergency out-of-band updates for Windows 10, Windows 11, and Windows Server to address credential prompt failures and issues preventing devices with Secure Launch enabled from shutting down or entering hibernation. Additionally, a known issue causing security applications to flag a core Windows component as vulnerable to memory corruption attacks was resolved on Patch Tuesday.
Key Takeaways
- Access your email accounts via webmail to avoid Outlook freezes.
- Move your Outlook PST files out of OneDrive to prevent unresponsiveness.
- Consider uninstalling the KB5074109 or KB5073724 updates, but be aware of potential security risks.
- Monitor for updates from Microsoft regarding a permanent fix for the Outlook freezing issue.
- Stay informed about other security updates that may affect your Windows devices.
Key Terms & Concepts
- KB5074109: In this article, KB5074109 refers to a Windows security update that has caused Outlook freezes for users with POP email accounts.
- PST files: PST files are personal storage table files used by Microsoft Outlook to store emails, contacts, and other data.
- OneDrive: OneDrive is a cloud storage service from Microsoft that allows users to store files and access them from multiple devices.
Read the original article here: https://www.bleepingcomputer.com/news/microsoft/microsoft-shares-workaround-for-outlook-freezes-after-windows-update/
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