Microsoft says uninstall Windows 11 KB5074109 to fix Outlook POP, PST hang, as 2026’s first update causes havoc

Microsoft advises users to uninstall Windows 11 KB5074109 to resolve freezing and hanging issues in Outlook Classic related to POP accounts and PST files. The update, released in January 2026, has caused various problems in Windows 11, including issues with Sleep mode and third-party apps saving files to cloud storage. Microsoft acknowledges the havoc caused by the update and recommends using webmail as a temporary workaround until a fix is available. Uninstalling the problematic update can restore Outlook Classic functionality, but users should be cautious about potential security risks associated with removing Windows updates.