Microsoft has identified an issue affecting Message Queuing (MSMQ) functionality in some enterprise environments after installing the December 2025 Windows security update (released December 9, 2025). Individuals using Windows Home or Pro editions on personal devices are very unlikely to experience this issue, as it primarily affects enterprise or managed IT environments.
To address this issue, an out-of-band (OOB) update has been released, today, December 18, 2025, on the Microsoft Update Catalog. For more information and installation instructions, refer to the appropriate KB article for each affected version of Windows listed below. For additional guidance, see How to download updates from the Microsoft Update Catalog.
- Windows 10, version 22H2 ESU and Windows 10 Enterprise LTSC 2021 (KB5074976)
- Windows Server 2019 and Enterprise LTSC 2019 (KB5074975)
- Windows Server 2016 and Windows 10 LTSB 2016 (KB5074974)
- Windows Server 2012 R2 (KB5074978)
- Windows Server 2012 (KB5074980)
- Windows Server 2008 R2 (KB5074977)
- Windows Server 2008 (KB5074979)