Update released on January 24, 2026 (KB5078127).

Question

Is the update released on January 24, 2026 (KB5078127) available for Windows 10 ?

Because, the problem with Outlook is also in Windows 10

Thanks.

Answer 1

The update released on January 24, 2026, is KB5078129, not KB5078127. This update addresses issues related to applications becoming unresponsive when saving files to cloud-backed storage, including Outlook configurations that store PST files on OneDrive. It is available for Windows 10, specifically for versions 22H2 and 21H2, as well as Windows 10 Enterprise LTSC 2021 and Windows 10 version 1809.

If you are experiencing issues with Outlook on Windows 10, it is recommended to install this update as it contains important improvements and resolutions for the described problems.

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References:

• Resolved issues in Windows 10, version 22H2
• Resolved issues in Windows 10 Enterprise LTSC 2021
• Resolved issues in Windows 10, version 1809 and Windows Server 2019

Answer 2

Hi ,

I'm Dyari. Thanks for reaching out. I will be happy to assist you in this regard.

January 24, 2026—KB5078127 update only applies to Windows 11 version 25H2, all editions, Windows 11 version 24H2, all editions.

https://support.microsoft.com/en-us/topic/january-24-2026-kb5078127-os-builds-26200-7628-and-26100-7628-out-of-band-cf5777f6-bb4e-4adb-b9cd-2b64df577491

However, January 24, 2026—KB5078129 applies to Windows 10 ESU and Windows 10 Enterprise LTSC 2021.

After installing the Windows update released on and after January 13, 2026, some applications became unresponsive or encountered unexpected errors when opening files from or saving files to cloud-based storage, such as OneDrive or Dropbox. In certain Outlook configurations that store PST files on OneDrive, Outlook may hang and fail to reopen unless the process is terminated or the system is restarted. Users may also see missing sent Items or previously downloaded emails being re‑downloaded.

https://support.microsoft.com/en-us/topic/january-24-2026-kb5078129-os-builds-19045-6812-and-19044-6812-out-of-band-cfbdbb30-81eb-49ff-ada2-c2af09aa7c1e

May I know what your Windows 10 edition and version are? What Outlook issue are you facing?

Answer 3

Hi Dyari,

Thank you for your reply.

My Windows 10 is 22H2.

It says here https://support.microsoft.com/en-us/topic/january-24-2026-kb5078129-os-builds-19045-6812-and-19044-6812-out-of-band-cfbdbb30-81eb-49ff-ada2-c2af09aa7c1e that update EKB KB5015684 is for Windows 10, version 22H2. How to I install it ?

Answer 4

And the issue with outlook is becoming unresponsive and / or redownloading the same emails again and again.