- Microsoft released an Out-of-band update (KB5078129) to patch bugs introduced by the January 2026 Patch Tuesday update.
- This update addresses apps dependent on cloud storage services on Windows 10.
Microsoft is now rolling out the Out-of-band (OOB) update KB5078129, available as builds 26200.6812 and 26100.6812 for Windows 10 22H1 and 21H2, to address a bug that prevents apps that use cloud storage (such as OneDrive and Dropbox) from working correctly, introduced with the January 2026 update.
On January 13, 2026, the software giant began rolling out the first Patch Tuesday Update of 2026 for Windows 10 and Windows 11, with new protections and improvements. However, this update also shipped with a known issue that made some apps unresponsive or caused unexpected errors when opening or saving files stored in cloud‑based locations.
In the Outlook app, for example, configurations that store PST files on OneDrive may hang and fail to reopen unless the process is terminated or the computer is restarted.
The update KB5078129 (builds 19045.6812 and 19044.6812) resolves this issue for affected devices that are enrolled in the Extended Security Updates (ESU) program, as support for Windows 10 has already ended on November 14, 2025.
Windows 10 22H2 update KB5078129
- Release date: January 24, 2027.
- Builds: 19045.6812 (22H2), 19044.6812 (21H2).
- Purpose: Fixes unresponsive or unexpected errors with some apps using cloud storage services introduced with the January 2026, Patch Tuesday update.
- Affected versions: Windows 10 22H2 and 21H2.
If you have a computer affected by these bugs, you should install this update immediately by going to Settings > Windows Update and clicking the “Check for updates” button.
Alternatively, you can download and install the update KB5078129 from the Microsoft Update Catalog for Windows 11.
This out-of-band update includes all fixes and improvements from the original January 2026 Security update, released January 13, 2026.
Out-of-band (OOB) updates explained
Out-of-band updates are emergency patches released outside the regular monthly schedule. Microsoft issues them to address urgent problems (such as newly discovered security flaws or critical bugs) that can’t wait for the next Patch Tuesday.
These updates are cumulative, meaning they include all previous fixes (security and non-security) plus the new targeted resolution.
Mauro Huculak is a Windows How-To Expert and founder of Pureinfotech in 2010. With over 22 years as a technology writer and IT Specialist, Mauro specializes in Windows, software, and cross-platform systems such as Linux, Android, and macOS.
Certifications: Microsoft Certified Solutions Associate (MCSA), Cisco Certified Network Professional (CCNP), VMware Certified Professional (VCP), and CompTIA A+ and Network+.
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