Microsoft has acknowledged a significant issue with the December 2025 Patch update (KB5071546) for Windows 10, affecting the Message Queuing (MSMQ) component, which is primarily used by enterprise applications. The update altered MSMQ's operational dynamics and modified NTFS permissions for its storage directory, requiring write access that many real-world implementations do not have. This has led to operational failures, with users experiencing error messages indicating insufficient resources. Reports indicate that uninstalling the update restores MSMQ functionality. Microsoft is investigating these issues, which also impact clustered MSMQ environments under load, but does not affect Windows 11. Users are advised to uninstall the update to resolve MSMQ issues.