Microsoft has issued a series of emergency out-of-band (OOB) cumulative updates to fix several disruptive bugs introduced in its January 13, 2026, security updates. Users and administrators reported widespread issues following the initial Patch Tuesday release, impacting multiple versions of Windows, including Windows 10, Windows 11, and Windows Server editions. The primary problems included failures with Remote Desktop connections, applications freezing when interacting with cloud storage services, and systems failing to shut down correctly. The new OOB updates, released on January 24, 2026, are designed to resolve these specific issues and are recommended for all affected customers.
It is important to note that these OOB updates do not address new security vulnerabilities. Instead, they fix functional regressions caused by the January 13 security patches. The key issues resolved include:
The issues affected a wide range of Microsoft operating systems. The new OOB updates apply to:
Administrators should consult the specific KB articles for their respective OS versions to determine applicability.
While not security-related, the impact of these bugs was significant for business operations. The inability to use Remote Desktop disrupted remote work and server administration for many organizations. Application hangs caused productivity losses and required IT support intervention. These issues demonstrate the delicate balance between deploying security patches promptly and ensuring system stability. The need for multiple OOB releases highlights the complexity of the Windows ecosystem and the challenges in testing updates across countless hardware and software configurations. For many system administrators, this event will cause them to re-evaluate their patch deployment rings, potentially delaying rollout to non-critical systems until the updates are proven stable.
The latest updates are cumulative, meaning they include all previous security fixes from the January 13 and January 17 releases, in addition to the new bug fixes. Key updates include:
These updates are available via the Microsoft Update Catalog and will be pushed through Windows Update for some users. However, they are considered optional preview releases, and administrators may need to seek them out manually.
Microsoft released a dedicated OOB update for the Outlook freezing bug, clarifying its cause (PSTs in cloud storage) and providing specific remediation steps.
New critical boot failures reported on Windows 11 after January updates, Microsoft investigating.
Apply the out-of-band updates provided by Microsoft to fix the functional regressions.
Mapped D3FEND Techniques:
The direct countermeasure to the issues caused by the January 13 updates is to apply the new out-of-band (OOB) software updates, specifically KB5078136 and KB5078238, provided by Microsoft. Patch management teams should prioritize the deployment of these corrective updates to systems confirmed to be experiencing the Remote Desktop or application hang issues. Before widespread deployment, it is crucial to test these OOB patches on a representative sample of pilot systems to ensure they resolve the target problems without introducing new regressions into the specific corporate environment. Organizations that paused their January patch cycle due to the reported bugs should now resume their deployment schedule using these revised cumulative updates. This incident underscores the importance of a phased or ring-based deployment strategy for all patches, allowing for issues to be caught in early deployment rings before they can cause enterprise-wide disruption.
Microsoft releases the initial January 2026 Patch Tuesday updates, which introduce several functional bugs.
Microsoft releases an initial OOB update to fix a system restart/shutdown bug.
Microsoft releases further OOB updates (KB5078136, KB5078238) to fix Remote Desktop and cloud storage issues.

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