Overview
- Microsoft confirms that Outlook Classic with POP3 profiles can freeze, fail to close properly, and refuse to relaunch after installing KB5074109 for Windows 11 24H2 and 25H2.
- Release Health notes warn that apps may hang when opening or saving files in cloud storage, with Outlook affected when PST files reside in OneDrive, causing missing Sent Items and repeated email downloads.
- Microsoft’s interim guidance advises moving PST files out of OneDrive, using webmail or alternative clients, or ending the Outlook process via Task Manager to regain access.
- Out-of-band updates have restored Windows App remote connections to Windows 365 and Azure Virtual Desktop and corrected shutdown/sleep issues on some builds, with the dedicated Remote Desktop client recommended as a workaround.
- A wide set of Windows client and server versions are impacted, the update addresses over 100 vulnerabilities including one exploited in the wild, and uninstalling the patch is discouraged as Microsoft works on further fixes.