Microsoft asks IT admins to reach out for Windows IIS failures fix

Microsoft warns that December 2025 updates (KB5071546/KB5071544/KB5071543) have introduced an MSMQ issue affecting Windows 10 22H2, Server 2019, and Server 2016, causing inactive queues, failed message writes, and IIS failures with misleading “insufficient resources” errors. The root cause is a change to the MSMQ security model and NTFS permissions requiring user write access to C:\Windows\System32\MSMQ\storage, also impacting clustered MSMQ under load. Microsoft has no fix timeline and advises enterprise customers to contact Microsoft Support for a temporary workaround or consider rolling back the updates.