Microsoft has hustled out an out-of-band update to address a Message Queuing issue introduced by the December 2025 update.

The patches, released for Windows 10 22H2 ESU, Windows 10 Enterprise LTSC 2021, and Windows 10 LTSB 2016, as well as flavors of Windows Server from 2008 to 2019, include the fixes from the December 9, 2025 update, but won't leave Message Queuing (MSMQ) in a broken state.

Administrators already dealing with the MSMQ issue can install this update to resolve it.

The problem mainly affected enterprise environments – according to Microsoft, users on Pro and Home editions of Windows were "very unlikely" to encounter the issue. The cause was a change that required MSMQ to have write access to areas where administrative restrictions usually apply. The result was that message queuing could stop working, leading to some distinctly unhelpful errors.

Services such as Microsoft's web server, Internet Information Services (IIS), could stop working, as could applications that need to write to queues. Worse, misleading logs were filled with text such as "There is insufficient disk space or memory," even though sufficient disk space and memory were available.

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It took Microsoft a few days to acknowledge there was a problem – the known issue was added to affected versions on December 12, 2025, during which time affected administrators were forced to deploy workarounds that involved either granting modified permissions to the storage folder or rolling back the update.

The out-of-band (OOB) update resolves the issue, though it calls into question Microsoft's quality practices once again, since a lot of corporate infrastructure depends on MSMQ.

Yes, the service has been around for a while (it dates back to the last century, to the days of Windows 95 and NT 4). There are alternatives for new development, but MSMQ remains a supported component of Windows. Its longevity means that applications where direct connectivity is not possible will likely depend on it for communication.

Affected users were understandably unhappy, with many having to field customer complaints as services fell over due to the issue.

While Microsoft's relatively swift resolution of the issue is laudable, the fact that it happened at all reflects poorly on the company's validation and quality control practices. Sure, MSMQ might not be a shiny new cloud component festooned with AI functionality, but plenty of enterprises have legacy code and applications that depend on it. Breaking it shows a level of carelessness that has not gone unnoticed. ®