Microsoft Windows & Native App Crashes: What's Gone Wrong in 2026

Overview

Microsoft has had a rough start to 2026 on Windows 11. After the January 13, 2026 Patch Tuesday updates, Microsoft published multiple known-issue notes and then shipped several out-of-band fixes to address regressions impacting everyday workflows like File Explorer reliability, cloud-file access, and Outlook data files. (See Microsoft’s KBs for Windows 11 23H2 and 24H2: KB5073455 and KB5074109.)

This post summarizes what broke, what Microsoft released to mitigate it, and what users and admins can do right now.

What Broke (The Practical Symptoms)

Reports varied by device and workload, but the most impactful issues clustered around:

• Apps closing unexpectedly during typing: Microsoft documented cases where apps (including Outlook, Teams, Edge, Chrome, and Excel) might close unexpectedly when entering text. (KB5073455)
• Cloud-file operations causing app hangs/errors: Microsoft documented a known issue where some applications may become unresponsive or error when opening/saving to cloud storage (for example OneDrive/Dropbox). In certain Outlook configurations where PST files are stored on OneDrive, Outlook may hang and fail to reopen until it’s terminated or the system restarts. (KB5074109, KB5077744)
• Explorer/taskbar instability: Microsoft shipped an optional preview update that calls out fixes for explorer.exe hangs and a missing taskbar in certain cases. (KB5074105)
• Remote Desktop / Secure Launch / power-related regressions: out-of-band updates were released to address specific regressions (including Remote Desktop sign-in failures and Secure Launch shutdown/hibernate issues). (KB5077744, KB5077797)
• Driver side-effects: Microsoft noted at least one case where a modem driver could be removed during the January update cycle. (KB5074109)

In some environments, even remediation (rollback) was messy: Windows Central reported Microsoft advised uninstalling a problematic update in some cases, and users ran into uninstall errors like 0x800f0905. (Windows Central)

What Microsoft Shipped (Timeline)

Here is the “patch + patch + patch” pattern that made this feel like an outage rather than a normal update cycle:

1. January 13, 2026 (Patch Tuesday): security updates land for Windows 11, including KB5073455 (23H2) and KB5074109 (24H2).
2. January 17, 2026 (out-of-band): KB5077744 (24H2/25H2) and KB5077797 (23H2) released to address specific regressions.
3. January 24, 2026 (out-of-band): KB5078127 and KB5078132 released; Microsoft notes fixes for the cloud-file / app hang scenarios tied to the January 13 update(s).
4. January 29, 2026 (optional preview): KB5074105 published with fixes that include Explorer/taskbar-related problems.

If you’re reading this later: always prefer the newest cumulative update(s) for your Windows version, since Microsoft tends to roll these fixes forward.

Impact on Users

The impact wasn’t just “a bug” - it hit core workflows:

• Work interruptions when Explorer hangs or the taskbar disappears.
• Data/workflow risk when cloud-file access causes apps to freeze or throw errors.
• Operational churn for admins: multiple emergency patches in short order, plus a rollback story that wasn’t always clean.

Microsoft’s Response

Microsoft’s response was mostly mechanical but effective: document the known issues, ship targeted out-of-band updates, and then roll fixes into later updates.

• Out-of-band update: KB5077797
• Out-of-band updates: KB5078127 and KB5078132
• Optional preview update: KB5074105

What You Can Do

If you’re encountering crashes or stability issues, consider:

1. Check your installed update(s): Settings -> Windows Update -> Update history.
2. Install the newest fixes available for your Windows version (including out-of-band updates if applicable). Start by reading the known issues/notes in KB5073455 (23H2) or KB5074109 (24H2).
3. If you’re hitting Explorer/taskbar issues, consider the newer preview update that includes Explorer fixes: KB5074105.
4. If Microsoft (or your internal IT) recommends it, uninstall the specific problematic update. Be aware there were reports of uninstall failures like 0x800f0905 in some cases. (Windows Central)
5. If you’re affected by the Outlook/cloud-storage scenario, Microsoft notes that moving PST files out of OneDrive can resolve Outlook-specific hangs in certain configurations. (KB5077744)
6. Back up critical data before major updates and keep restore points available where practical.

These steps can help mitigate disruption while awaiting fuller stability improvements from Microsoft.

Final Thoughts

The early-2026 Windows 11 update cycle is a reminder that “core OS plumbing” bugs (Explorer, file access, drivers) can have outsized downstream impact. Even when fixes arrive quickly, the cumulative disruption is real - especially for businesses that can’t afford a week of uncertain patching.

The good news is that Microsoft documented the issues and shipped multiple targeted updates. The practical takeaway is to treat Patch Tuesday as an operational change window: stage, validate, and keep a rollback plan that actually works on your fleet.

References

Major News & Reports

• Microsoft Support: Windows 11 23H2 update history (January 13, 2026) - KB5073455
• Microsoft Support: Windows 11 24H2 update history (January 13, 2026) - KB5074109
• Microsoft Support: Out-of-band update (January 17, 2026) - KB5077797
• Microsoft Support: Out-of-band update (January 17, 2026) - KB5077744
• Microsoft Support: Out-of-band update (January 24, 2026) - KB5078127
• Microsoft Support: Out-of-band update (January 24, 2026) - KB5078132
• Microsoft Support: Optional preview update (January 29, 2026) - KB5074105
• Windows Central: uninstall/rollback guidance and uninstall error reports around KB5074109 - article

Supplementary Sources

• TechRadar: Explorer crash/hang fix coverage (ties to KB5074105) - article