September Windows Server updates break Remote Desktop Services
The September 2026 cumulative updates for Windows Server 2019, 2022, and 2025 are causing Remote Desktop Services (RDS) failures. After installing these updates, RDS initially works but then starts failing after a few hours or after users log out, preventing new connections and causing existing sessions to hang. Some administrators report that the only way to restore functionality is a hard reset. Rolling back the updates restores RDS functionality but removes the security fixes. Microsoft has not yet confirmed the cause or provided a fix.
AI Analysis
Technical Summary
Windows Server 2019, 2022, and 2025 systems experience Remote Desktop Services failures following the installation of the September 2026 Patch Tuesday cumulative updates (KB5122876, KB5122882, KB5122871 respectively). Users report that RDS works initially but then fails after some time or after user logouts, with new connection attempts hanging and existing sessions unable to disconnect properly. Debugging from one administrator suggests a deadlock between Remote Desktop and the Local Session Manager, specifically hanging at RDPSERVERBASE!WDLIB_Close, though Microsoft has not confirmed this. Rolling back the updates restores functionality but removes the security patches.
Potential Impact
The issue disrupts Remote Desktop Services on affected Windows Server versions, preventing users from connecting remotely and causing existing sessions to hang. This can lead to operational downtime and may require hard resets to restore service. Rolling back the updates removes the security fixes, potentially exposing systems to vulnerabilities addressed by the September 2026 patches.
Mitigation Recommendations
Currently, no official fix or mitigation has been confirmed by Microsoft. Administrators experiencing these issues have found that rolling back the September 2026 cumulative updates restores Remote Desktop Services functionality. However, this also removes the security patches included in these updates. Monitor official Microsoft communications for updates and patches addressing this issue before reapplying the updates.
September Windows Server updates break Remote Desktop Services
Description
The September 2026 cumulative updates for Windows Server 2019, 2022, and 2025 are causing Remote Desktop Services (RDS) failures. After installing these updates, RDS initially works but then starts failing after a few hours or after users log out, preventing new connections and causing existing sessions to hang. Some administrators report that the only way to restore functionality is a hard reset. Rolling back the updates restores RDS functionality but removes the security fixes. Microsoft has not yet confirmed the cause or provided a fix.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Windows Server 2019, 2022, and 2025 systems experience Remote Desktop Services failures following the installation of the September 2026 Patch Tuesday cumulative updates (KB5122876, KB5122882, KB5122871 respectively). Users report that RDS works initially but then fails after some time or after user logouts, with new connection attempts hanging and existing sessions unable to disconnect properly. Debugging from one administrator suggests a deadlock between Remote Desktop and the Local Session Manager, specifically hanging at RDPSERVERBASE!WDLIB_Close, though Microsoft has not confirmed this. Rolling back the updates restores functionality but removes the security patches.
Potential Impact
The issue disrupts Remote Desktop Services on affected Windows Server versions, preventing users from connecting remotely and causing existing sessions to hang. This can lead to operational downtime and may require hard resets to restore service. Rolling back the updates removes the security fixes, potentially exposing systems to vulnerabilities addressed by the September 2026 patches.
Defensive Guidance
Currently, no official fix or mitigation has been confirmed by Microsoft. Administrators experiencing these issues have found that rolling back the September 2026 cumulative updates restores Remote Desktop Services functionality. However, this also removes the security patches included in these updates. Monitor official Microsoft communications for updates and patches addressing this issue before reapplying the updates.
Technical Details
- Classification
- {"confidence":0.3,"severitySource":"default","classifier":"rss-v2"}
- Article Source
- {"url":"https://www.bleepingcomputer.com/news/microsoft/september-windows-server-updates-break-remote-desktop-services/","fetched":true,"fetchedAt":"2026-09-10T20:46:56.912Z","wordCount":740}
Threat ID: 6aa3174091cc7f3848b512c0
Added to database: 09/10/2026, 20:46:56 UTC
Last enriched: 09/10/2026, 20:47:01 UTC
Last updated: 09/10/2026, 20:47:01 UTC
Views: 1
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