KB5074109 Regression: Outlook PST in OneDrive Hangs After January 2026 Update

Microsoft’s January servicing wave has produced a messy and consequential regression: a cumulativetive update released on January 13, 2026 (KB5074109) introduced a file-access problem that can leave apps — most notably classic Microsoft Outlook when its PST files live in OneDrive or other cloud-synced folders — freezing, failing to save, or re-downloading messages, and Microsoft’s emergency responses and interim guidance have left administrators and users juggling security vs. stability decisions.

---

Background / Overview​

The monthly Patch Tuesday cumulative for Windows published on January 13, 2026 arrived as a combined package (SSU + LCU) that Microsoft shipped to multiple servicing branches. The package identified as KB5074109 corresponds to OS builds 26200.7623 and 26100.7623 for affected Windows 11 channels. Within days of deployment, telemetry and community reports converged on several serious regressions: Remote Desktop/Cloud PC credential failures, a Secure Launch configuration-specific shutdown/hibernate regression, and an application file-I/O problem that causes apps to hang when opening or saving files that reside in cloud-synced locations such as OneDrive or Dropbox.
Microsoft pushed targeted out-of-band (OOB) cumulative updates on January 17, 2026 to remediate the highest-impact platform regressions (for example, KB5077744 and KB5077797 depending on the branch), but the Outlook/PST-in-cloud hang remained listed as investigating and required distinct mitigations.

---

What exactly broke: Outlook, PSTs and cloud-synced storage​

Symptoms users and admins are seeing​

• Classic Outlook (Win32) with POP profiles or PSTs stored in OneDrive can hang or become unresponsive; Outlook windows may show “Not Responding,” and closing the UI can leave a lingering OUTLOOK.EXE process that prevents a normal restart.
• Sent messages may not appear in Sent Items, even though they were sent; message state and local indexes can be inconsistent.
• Previously-downloaded messages sometimes re-download, indicating local state or index corruption or a failure to persist write operations.
• Other apps that perform file I/O against cloud-backed folders (save/open operations in OneDrive/Dropbox) have reported timeouts or hangs in the same timeframe, pointing to a shared underlying surface.

The most frustrating practical outcome​

For affected Outlook users the only reliable way to restore function is either to forcibly kill the Outlook process via Task Manager or to reboot the PC — neither of which is acceptable in production environments where data integrity and audit trails matter. Microsoft’s short-term guidance has included moving PST files out of OneDrive and using webmail as an alternative client, which is functionally a workaround but not a fix for users relying on local PST-based workflows.

---

Scope: which Windows and Outlook configurations are impacted​

• Windows branches affected include Windows 11 versions 25H2, 24H2 and 23H2 (the January cumulative/SSU packaging varies per branch) and reports indicate similar symptoms on Windows 10 22H2 and certain LTSC/ESU channels.
• Outlook surface: classic Outlook (Outlook for Microsoft 365 — Win32) using POP3 profiles or PST files stored in cloud-synced directories (OneDrive/Dropbox) is the principal surface Microsoft has acknowledged; other legacy flows (local PST access patterns) are implicated.

These are configuration-dependent failures: not everyone who installed the January cumulative will see the issue, but when it appears the effects are disruptive and persistent until mitigated.

---

Timeline of events (concise)​

• January 13, 2026 — Microsoft releases the January cumulative update KB5074109 (SSU + LCU) for Windows servicing branches. Administrators begin deployment via Windows Update, WSUS and Microsoft Update Catalog.
• Within hours–days — Community and enterprise telemetry report multiple regressions: Remote Desktop credential failures, Secure Launch shutdown/hibernate issues on select 23H2 devices, and application hangs when saving or opening files in cloud-synced locations; classic Outlook POP/PST hangs become widely reported.
• January 17, 2026 — Microsoft issues targeted out‑of‑band updates (for example KB5077744 and KB5077797) to remedy Remote Desktop and Secure Launch regressions; issues tied specifically to Outlook/PST-in-cloud remain under investigation and are subject to interim guidance.

---

Technical analysis: why PSTs plus OneDrive is fragile (and why the update likely exposed it)​

The PST file format and local atomicity assumptions​

PST is a legacy single-file mailbox store with tight expectations about local, synchronous file access. Outlook assumes it has exclusive, reliable file handles when writing indexes, updating message state, and performing transactional operations. Interference with those assumptions — for example, placeholder semantics, delayed write-through, or file-lock mediation by a sync client — can cause Outlook’s internal state machine to block, wait indefinitely, or write partially completed metadata.

Cloud sync clients interpose on file streams​

OneDrive and similar sync clients introduce layers that may implement placeholder files, delayed hydration, or on-demand streaming of content. Those behaviors change timing and locking characteristics for applications that expect a POSIX/Win32 atomic local file. A small timing change in the OS file system filter stack or associated APIs can push a previously acceptable interaction into deadlock, race or failure. The pattern reported (hangs, not saving, re-downloads) strongly implicates an interaction between PST I/O assumptions and the OneDrive sync driver / placeholder semantics.

Why a cumulative update would surface this now​

Large cumulative updates like KB5074109 bundle changes across the servicing stack, file system drivers, and user-mode components. When Microsoft combines an SSU and an LCU in a single payload the surface area for regressions increases: timing changes, new ordering of initialization routines, or subtle API behavior changes can expose previously unexercised code paths in both first-party and third-party software. Known Issue Rollback (KIR) exists precisely because uninstalling an entire SSU/LCU blend is operationally fraught; KIR lets Microsoft surgically disable the problematic change without fully removing security fixes. However, when the root cause spans app semantics, sync clients, and OS changes, KIR alone may not be sufficient.

---

Microsoft’s public guidance and interim mitigations​

Microsoft’s official, immediately actionable guidance included a set of expected but blunt mitigations:

• Move PST files out of OneDrive (or any cloud‑synced folder) into a local folder that OneDrive does not manage; this restores Outlook’s direct local I/O semantics for many impacted users. Microsoft explicitly recommended this as a temporary workaround while engineering investigates.
• Use webmail as an alternate client when Outlook is locked up and you need to continue sending/receiving mail without the desktop client. Microsoft suggested contacting the application developer if other methods to open or save data are required — advice that is circular when Microsoft is both the OS and the application vendor.
• Known Issue Rollback (KIR) and Group Policy artifacts for enterprise fleets where Microsoft offered a targeted rollback that disables the underlying change causing some of the authentication/remote-access regressions. Administrators were directed to KIR where appropriate instead of uninstalling LCUs.
• Out-of-band updates for other regressions (Jan 17, 2026) such as KB5077744 and KB5077797 fixed Remote Desktop and Secure Launch issues but did not universally resolve the Outlook PST cloud access hang.

What Microsoft did not and could not recommend​

Microsoft correctly avoided recommending uninstalling the entire cumulative for many organizations because that action can reintroduce the security vulnerabilities that the LCU was intended to address. Microsoft documented DISM-based removal approaches for LCUs where necessary and cautioned administrators about the tradeoffs — removing an LCU may be operationally possible, but doing so increases exposure to fixed vulnerabilities.

---

Practical remediation checklist (for users and administrators)​

Follow these prioritized steps based on environment and risk appetite:

• Pause and pilot — Do not rush to broad rollout of KB5074109 across production rings until you validate in a pilot pool. Staged deployment remains the most reliable defense.
• If you see Outlook hangs and you use PSTs in OneDrive:
• Move PST files out of OneDrive to an unsynced local folder (for example C:\Users\<user>\Documents\PST‑Local) and update Outlook profile to point to the new location. This is the simplest immediate mitigation.
• If moving PSTs is not feasible, instruct users to use Outlook Web Access (webmail) until a permanent fix is available.
• Enterprise controls:
• Deploy Microsoft’s KIR Group Policy artifacts where KIR is provided for the specific regression instead of uninstalling the LCU. This provides targeted behavioral rollback without removing security fixes.
• Keep device drivers and sync client versions current; some regressions are mitigated by updated OneDrive clients or vendor drivers.
• If you must remove the LCU:
• Follow Microsoft’s documented DISM / Remove‑Package sequence carefully and be prepared to accept the security tradeoffs; collect CBS/DISM logs before and after for diagnostics. Example commands appeared in deployment guidance from Microsoft (use exact filenames from the Update Catalog when applying MSUs or when removing packages).
• Collect diagnostics:
• When reporting the issue, gather process dumps, OneDrive logs, Outlook crash/hang dumps, and Windows Event logs — these drastically reduce triage time for both vendor support and internal teams.

---

Risk analysis: security vs. operational stability​

• Removing the cumulative (LCU) to regain application stability exposes systems to the security holes fixed by that update. For many organizations the risk of reintroducing known vulnerabilities is unacceptable, especially on internet-facing or regulated systems. Microsoft’s guidance reflects this tension and encourages KIR where possible.
• Forcing Outlook processes to terminate to recover a hung user session risks PST corruption if the process was mid-write. Recovered users who experience corrupted PSTs then require repair operations that cost time and sometimes data. Microsoft’s recommendation to avoid force-termination unless necessary is therefore prudent.
• Moving PSTs out of OneDrive preserves functionality but forces a change in established user workflows, storage policies, and backup patterns; many businesses place PSTs in OneDrive precisely because it centralizes and backs up those files. The workaround trades one operational convenience (cloud backup) for immediate availability.

---

Why this episode matters beyond a single bug​

This is not merely an Outlook story. The incident exposes systemic tensions in modern OS servicing:

• Large, combined update packages (SSU + LCU) change many moving parts at once; when millions of configurations exist in the wild even low-probability interactions will surface.
• Legacy application semantics (like PST’s expectation of local atomic writes) are fragile when layered with new platform features (on-demand file hydration, placeholder files, advanced power security features). The interaction between old and new code is a recurring source of regressions.
• Serviceability tools like KIR are necessary but not universally sufficient — they help address behavioral regressions, but when the root cause spans multiple components the path to a clean remediation is more complex and requires coordinated fixes across OS, sync client, and app teams.

---

Short‑ and medium‑term recommendations for organizations​

• Prioritize pilot deployments and broaden telemetry coverage (collect process dumps, user-mode traces, OneDrive and Outlook logs) during the next Patch Tuesday cycle.
• Maintain golden images and WinRE images prior to injecting new SSUs/LCUs; have a pre-tested rollback plan for critical systems.
• Re-evaluate reliance on PST-based workflows: where possible, migrate data to server-hosted mailboxes (Exchange Online/On‑Prem Exchange with OST) that avoid PST file fragility and rely less on local file semantics.
• For managed fleets, adopt KIR-driven mitigations when Microsoft provides them rather than broad uninstall procedures.

---

What we still don’t know (and cautions about unverifiable claims)​

• Public advisories and community reporting make the linkage between KB5074109 and Outlook/PST-in-cloud hangs clear, but the precise root-cause code paths (e.g., whether the regression is in the OS file system filter, OneDrive placeholder handling, or Outlook’s I/O path) remain part of Microsoft’s internal investigation and the engineering remediation. When vendor advisories mark an issue as investigating, absolute technical attribution should be treated as provisional.
• A widely circulated sidebar in industry commentary links the regression wave to broader quality-control concerns, and some pieces reference executive claims about AI-generated code (for example an unverifiable attribution that "30% of Microsoft’s code was written by AI"). That specific claim is not corroborated in the technical advisories examined here and should be treated cautiously until independently verified. Any attempt to blame a single organizational cause without direct evidence risks conflating correlation with causation. Treat such claims as anecdotal unless Microsoft or multiple primary sources explicitly confirm them.

---

Final assessment and takeaways​

• The January 13, 2026 cumulative update (KB5074109) touched a broad set of platform components and — as sometimes happens with large, complex rollouts — exposed fragile interactions between legacy application semantics (Outlook PST) and modern cloud-file synchronization mechanics (OneDrive/Dropbox placeholder/hydration). The result was a serious productivity-impacting regression for a subset of users; Microsoft acknowledged the issue and provided interim mitigations while issuing targeted emergency updates for related regressions.
• The pragmatic response for administrators is conservative: pause and pilot, prefer KIR where available, and avoid uninstalling LCUs unless the organization explicitly accepts the re-exposure to fixed vulnerabilities. End users relying on PST-based workflows must consider moving PSTs out of cloud-synced folders or migrating to server-hosted mailboxes.
• This episode should prompt a renewed emphasis on cross-team testing that includes real-world sync clients and legacy application workflows as part of platform-level validation. The coexistence of legacy file formats and modern cloud services is a long‑term compatibility surface — not a one-time test case — and needs to be treated as such by vendors and IT teams alike.

Microsoft has signaled it is actively working on a resolution and will provide updates when a permanent fix is available. In the meantime, the combination of careful staging, KIR where possible, and pragmatic local-workflow adjustments will be the safest path for organizations balancing security and productivity in the wake of this January servicing wave.

---

Quick reference: actionable next steps (one-page)​

• If you manage endpoints:
• Pause broad rollout of KB5074109.
• Pilot KB5074109 in a controlled ring with Office/OneDrive telemetry enabled.
• Deploy KIR artifacts where available instead of uninstalling LCUs.
• If you are an end user experiencing Outlook hangs:
• Move PSTs out of OneDrive to a local folder and update Outlook profile.
• Use webmail until a fix is published if moving PSTs is not possible.
• Avoid force-killing OUTLOOK.EXE unless absolutely necessary to reduce corruption risk.
• If you are a security/ops lead:
• Weigh the risk of uninstalling LCUs vs. the operational cost of the outage; treat removal as last resort.
• Ensure logging, process dump, and OneDrive diagnostic collection are available for triage.

This is a live servicing incident: monitor Microsoft’s Release Health and support advisories for permanent remediation and KIR artifacts for your servicing branch.

---

Source: How-To Geek Saving files is currently broken on Windows 11 and Windows 10

 

[ChatGPT]

Microsoft has told affected users to remove the Windows 11 January 2026 cumulative update (KB5074109) after widespread reports that the patch is causing serious stability and application failures — most notably rendering Classic Outlook profiles using POP accounts or local PST files unusable when those PSTs are stored in cloud‑synced folders such as OneDrive.

Background​

Microsoft released the January 2026 security update (identified as KB5074109) on January 13, 2026 as part of its regular Patch Tuesday roll‑out. The update shipped as combined servicing stack and cumulative packages for multiple Windows 11 servicing channels and included fixes and security improvements across client and server SKUs; the affected OS builds include reported LCU build numbers 26200.7623 and 26100.7623.
Within days of the rollout, end users and IT teams began reporting a variety of failures: Outlook Classic hangs and fails to exit properly, repeated redownloading of messages, desktop black screens or resets of desktop settings, File Explorer customisations being lost, and third‑party and system applications freezing when attempting to open or save files stored in cloud‑backed folders such as OneDrive and Dropbox. Independent outlets and community testing reproduced many of these symptoms and documented the patterns.
Microsoft has published support advisories acknowledging the issues, describing observed symptoms and affected configurations, and issuing short‑term workarounds — including using webmail, relocating PST files out of cloud‑synced folders, and, in the most disruptive cases, uninstalling the January update until a fix ships. The company has also signalled it is actively investigating a long‑term remediation.

---

What exactly is breaking — symptoms and scope​

Outlook Classic: the most visible casualty​

The clearest and most widely reported problem is with Classic Outlook (Outlook desktop) profiles that rely on POP accounts or local PST files — especially where PSTs are stored in OneDrive or other cloud‑sync folders. Reported symptoms include:

• Outlook windows that hang and display “Not Responding”.
• Inability to restart Outlook without terminating Outlook.exe in Task Manager or rebooting the machine.
• Sent messages not appearing in Sent Items despite being sent.
• Previously downloaded messages re‑downloading repeatedly.
• Random freezes during send/receive operations.

Microsoft’s support documentation specifically calls out these scenarios and lists webmail and PST relocation as the immediate mitigations for impacted users.

Cloud‑backed file access and application instability​

Beyond Outlook, multiple reports describe applications freezing or erroring when accessing files stored in cloud‑synced folders (OneDrive, Dropbox). In some cases the system shows a temporary black screen before the desktop fully loads; in others, desktop wallpaper and personalization settings are reset. These errors appear related to file I/O operations crossing the local/cloud boundary after the January update. Evidence of repeated, real‑world occurrences has been collected by researchers and technology publications.

Who is affected​

• Home users who use Classic Outlook with POP accounts and keep PST files inside OneDrive or other sync clients are at high risk of encountering the Outlook hang.
• Small businesses that rely on PSTs or older POP workflows are also likely to be impacted if PSTs live in cloud folders.
• Enterprise environments can see a broader surface area: Remote Desktop, Azure Virtual Desktop, and Windows 365 related sign‑in issues were also reported after the same update in certain configurations, prompting out‑of‑band emergency fixes for those particular scenarios.

---

Why the update likely caused these problems (what we know and what we don’t)​

Microsoft’s public advisories describe observed behavior and provide mitigation steps, but they do not publish a full post‑mortem until engineering completes the investigation. Independent reporting and initial technical analysis by several outlets suggest the update likely introduced a change in a low‑level component that manages file access or security checks for cloud‑backed storage — creating deadlocks or access conflicts when an application like Outlook attempts to open PST containers that are actively synchronised. That hypothesis explains why PST files in OneDrive are especially problematic. However, this remains a working theory and should be treated as unverified technical speculation until Microsoft publishes root‑cause details.
Strength of evidence:

• Confirmed: the update date and KB number, the list of common symptoms, and Microsoft’s mitigation guidance.
• Probable but unconfirmed: exact code path or API change that triggers deadlocks. Several credible outlets and community diagnostic threads have converged on file‑I/O conflicts as the likely culprit, but a definitive, engineering‑level explanation is not yet public. Treat any specific “root cause” claim as tentative until Microsoft produces a technical postmortem.

---

Official guidance and Microsoft’s recommended actions​

Microsoft’s published guidance for impacted users lists three main short‑term options:

• Use the Outlook web app (webmail) temporarily to avoid the desktop client hang.
• Move local PST files out of cloud‑synced folders (for example, relocate PSTs to a purely local folder that OneDrive does not sync).
• Uninstall the January 2026 cumulative update (KB5074109) if workarounds are insufficient and the update is causing severe disruption. Microsoft warns that uninstalling a security update increases exposure to vulnerabilities addressed by the patch and frames removal as a temporary, high‑cost mitigation.

Microsoft is also deploying targeted mitigations for enterprise environments where feasible, such as Known Issue Rollback (KIR) and out‑of‑band patches to address specific customer impact areas. Administrators should monitor the Windows release health dashboard and Microsoft Update guidance for those enterprise controls.

---

Practical, verified steps for users and IT admins​

The following steps are practical, platform‑tested actions that users and administrators can take now. Each step references the relevant Microsoft or widely accepted vendor guidance.

For home users and small businesses (non‑managed devices)​

• Confirm whether KB5074109 is installed: open Settings > Windows Update > Update history and look for January 13, 2026 entries or KB5074109. If you prefer command‑line, tools and commands that list installed HotFix/KBs can be used.
• If you use Classic Outlook with PSTs stored in OneDrive, immediately move PST files to a local folder that is not synchronized by OneDrive. Then open Outlook from that machine. Microsoft’s support article includes this as a recommended workaround.
• If moving PSTs is not possible or practical, switch to Outlook Web Access (webmail) for critical email operations until a permanent fix is available. This avoids the desktop client deadlocks.
• If the update is causing system instability beyond Outlook (e.g., frequent crashes, black screens), consider uninstalling KB5074109 as a temporary step. Use Settings > Windows Update > Update history > Uninstall updates to remove the cumulative update, then reboot. Microsoft documents the uninstall path and explicitly warns about security trade‑offs.

For enterprise IT and managed environments​

• Evaluate Known Issue Rollback (KIR) options and Group Policy mitigations that Microsoft is offering for certain scenarios; Microsoft has published Group Policy packages and KIR instructions for enterprise deployment tied to this update. Apply only the packages appropriate for your Windows servicing channel and test in a lab before broad deployment.
• If devices are managed with WSUS, SCCM (ConfigMgr), or patch management tools, consider using those platforms to:
• Temporarily block the problematic KB from deployment.
• Stage the rollback on a pilot ring and validate remediation.
• Use Windows Update for Business or Group Policy to defer quality updates while you assess the impact.
• To block a specific KB centrally, vendors and community documentation show two common approaches:
• Use PSWindowsUpdate or the PSWindowsUpdate module to hide a specific KB from Windows Update on endpoints. This requires administrative scripting and testing.
• Configure your management infrastructure (WSUS/ConfigMgr) to decline or withhold the specific KB, and use patch‑management automation to ensure devices do not receive the KB pending remediation.
• If uninstalling is required but the GUI does not offer an uninstall option for the combined package, the Microsoft guidance for removing the LCU from a combined package indicates using DISM/Remove‑Package against the LCU package name or relying on Windows Recovery options for extreme cases. Administrators should consult Microsoft support guidance and test the process in a non‑production environment before applying broadly.

---

Risk assessment: the trade‑offs of uninstalling a security update​

Uninstalling a security update is never a no‑cost action. Microsoft explicitly warns users to understand the risks before removing security patches: the system will revert to a state that lacks the protections included in the update. For many users the immediate operational disruption may make the risk acceptable in the short term, but every decision should weigh:

• The severity and exploitability of the vulnerabilities fixed by KB5074109 (public CVE details will determine real exposure).
• The operational impact of the bug (if Outlook is core to daily business, downtime costs can outweigh short‑term security exposure).
• The availability of safer mitigations (moving PSTs, using webmail, KIRs) that avoid removing the update entirely.

IT leaders should treat the uninstall as a temporary triage step and plan for rapid re‑application of the security update once Microsoft supplies a corrected cumulative update or KIR is deployed.

---

Quality control and the broader context: what this says about Windows update reliability​

This incident is the latest in a series of high‑impact updates that required rapid follow‑ups or rollbacks. Across 2024 and 2025, the Windows servicing pipeline experienced several notable regressions that prompted emergency patches and targeted mitigations. The recurrence of such events has several practical causes and policy implications:

• Complexity: cumulative updates touch many subsystems and drivers; the attack surface for regressions rises with breadth.
• Telemetry and validation: automated testing improves, but real‑world environment diversity can expose cases that pre‑release testing missed.
• Rapid delivery cadence: the push to ship monthly cumulative updates, sometimes combined with servicing stack changes, compresses engineering and validation cycles.
• Cloud‑file integration: as more users store data in cloud‑synced folders, subtle interactions between sync clients and legacy desktop apps create novel failure modes.

These systemic realities argue for defenders adopting layered mitigation strategies: stronger isolation for legacy PSTs, migration away from POP/PST workflows toward server‑side (IMAP/Exchange/Microsoft 365) mail, and robust pilot/test rings for updates in managed environments.

---

Practical recommendations — short checklist​

• If you use Classic Outlook with PSTs in OneDrive: immediately move PSTs to a local folder and stop syncing them. Test Outlook functionality before re‑enabling sync.
• If Outlook is unusable and PST relocation is not feasible: switch to Outlook Web App until Microsoft issues a fix.
• If you are experiencing system instability beyond email: consider uninstalling KB5074109 using Settings > Windows Update > Update history > Uninstall updates, but treat this as a last‑resort step and document business risk.
• For managed fleets: apply Known Issue Rollback Group Policy packages where available; use WSUS/ConfigMgr or PSWindowsUpdate to withhold the KB from broader deployment until validated.
• Monitor Microsoft’s Windows release health dashboard and the official Microsoft support entries for the KB — those pages will carry the authoritative mitigation and patch guidance.

---

What to watch next​

• A confirmed engineering root‑cause post from Microsoft that explains the exact code change and the corrective measure. Until that appears, all technical explanations are provisional.
• A cumulative update or KIR roll‑out that restores normal behavior without forcing wholesale uninstalls. Microsoft has indicated a future fix is planned; administrators should schedule rapid validation when that fix is available.
• Any disclosure of security consequences for devices that remain on unpatched systems. If public CVEs tied to the January update are marked as actively exploited, the calculus around removing the KB will change substantially.

---

Final analysis — balancing reliability, security, and operational continuity​

The January 2026 KB5074109 incident reinforces a recurring truth for Windows administrators and power users: security updates are essential, but they are not risk‑free. When a security patch introduces regressions that materially impair business workflows — particularly in a core productivity app like Outlook — organizations face a painful but necessary triage between security and availability.

• Short‑term mitigation: Microsoft’s pragmatic advice — move PSTs out of cloud sync, use webmail, or uninstall where necessary — is the correct triage for urgent operational continuity. These steps are simple to execute and can remove the immediate blockers for most users.
• Medium‑term: IT should adopt selective blocking and pilot testing as part of a disciplined patch management posture. Use Known Issue Rollback or targeted Group Policy packages as available to avoid broad uninstalls.
• Long‑term: reduce reliance on legacy PST/POP workflows that put brittle state on the client. Migrate critical mailboxes to server‑side storage when possible, and design backups and incident plans that assume a monthly update cycle may bring occasional disruption.

This event is a call to action for administrators and power users: validate your update strategy, protect legacy data stores from cloud interaction risks, and expect that occasional rollback decisions will be part of modern patch operations. Microsoft's transparency in acknowledging the problem and providing workarounds is welcome, but the community and enterprise teams must now operationalize that guidance to preserve both security and productivity.

---

Microsoft is continuing its investigation and will publish patches and guidance as fixes are completed. Users and administrators should follow official Windows release health advisories and their internal change‑management channels before applying or removing enterprise updates.

---

Source: Daily Times Microsoft advises uninstalling Windows 11 January update after major glitches - Daily Times