queue persistence

Queue persistence in Windows environments refers to the ability of Microsoft Message Queuing (MSMQ) to reliably store messages on disk. A December 2025 security update from Microsoft introduced a regression that altered NTFS permissions, breaking queue persistence for many administrators. This caused IIS-hosted applications and legacy middleware to fail when writing to queues, displaying misleading "insufficient resources" errors. Microsoft acknowledged the issue, added it to affected KB articles, and offered mitigations through support channels while working on an official fix. The incident highlights the critical role of queue persistence in enterprise messaging and the impact of security patches on production systems.