KB5077795 (OS Build 17763.8280) Out-of-Band Update for Windows 10 LTSC 2019 and Server 2019
Out-of-band update released January 17, 2026, for Windows 10 Enterprise LTSC 2019 and Windows Server 2019, fixing Remote Desktop sign-in failures at OS build 17763.8280.
Summary
KB5077795 is an out-of-band update for Windows 10 Enterprise LTSC 2019 and Windows Server 2019, released on January 17, 2026, bringing the OS to build 17763.8280. It targets a specific Remote Desktop sign-in failure and builds on the January 13, 2026 cumulative update KB5073723. Source: Microsoft Support.
Improvements and fixes
- Remote Desktop sign-in failures fixed: Some users encountered sign-in failures when establishing Remote Desktop connections. The failure affected authentication steps across different Remote Desktop applications on Windows, including the Windows App. This update resolves that behavior.
- This update also incorporates all fixes and improvements that were included in the January 13, 2026 cumulative update KB5073723 (OS Build 17763.8276). If earlier updates are already installed, only the new content in this package is downloaded and applied.
Known issues
Japanese characters fail to render correctly in PowerShell
Symptom: On Japanese language installations of Windows Server 2019, after installing updates released on or after January 13, 2026, Japanese characters may not display correctly in the PowerShell console. An unintended change incorrectly sets PowerShell encoding to UTF-8 after installation. English text and command entry continue to work normally, but Japanese output appears garbled or as question marks. Japanese text typed into PowerShell is affected in the same way.
Workaround: This issue is resolved in Windows updates released on and after April 14, 2026, such as KB5082123. Microsoft recommends installing the latest Windows update, which includes this resolution.
Apps might become unresponsive when saving files to cloud-based storage
Symptom: After installing this update, some applications may become unresponsive or encounter unexpected errors when opening or saving files to cloud-based storage such as OneDrive or Dropbox. In certain Outlook configurations where PST files are stored 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.
Workaround: This issue is addressed in KB5078131.
Some devices with Virtual Secure Mode enabled might fail to shut down or hibernate
Symptom: After installing this update, some Secure Launch-capable PCs with Virtual Secure Mode (VSM) enabled are unable to shut down or enter hibernation. Instead of shutting down or hibernating, the device restarts.
Workaround: This issue is addressed in KB5075904.
How to get this update
Prerequisite: You must have installed the August 10, 2021 servicing stack update (SSU) KB5005112 before applying this cumulative update.
This update is available through the following channels:
- Windows Update and Windows Update for Business - available via the Update Catalog.
- Microsoft Update Catalog - download the standalone package directly from the Microsoft Update Catalog website.
- Windows Server Update Services (WSUS) - available via the Update Catalog.
This update also includes a combined servicing stack update (SSU KB5074222, version 17763.8260). Microsoft now ships the latest SSU together with the latest cumulative update to improve update reliability. If you need to remove the cumulative update after installation, use the DISM /Remove-Package command with the LCU package name. Running wusa.exe /uninstall on the combined package will not work because the SSU is included and cannot be removed after installation.
Frequently asked questions
Why was this update released out-of-band rather than on Patch Tuesday?
Microsoft releases out-of-band updates when a specific, high-priority issue needs to be resolved before the next scheduled monthly update. In this case, Remote Desktop sign-in failures affecting authentication across multiple Remote Desktop applications warranted an immediate fix rather than waiting for the February 2026 update cycle.
Does this update replace the January 2026 cumulative update, or is it additive?
KB5077795 builds on and includes everything from the January 13, 2026 cumulative update KB5073723 (OS Build 17763.8276). If that update is already installed, only the new content in KB5077795 - specifically the Remote Desktop fix - is downloaded and applied to the device.
Do I need to install any prerequisite before applying KB5077795?
Yes. Microsoft requires that the August 10, 2021 SSU (KB5005112) be installed on the device before this cumulative update can be applied. The package also ships with SSU KB5074222 (version 17763.8260) bundled inside, which improves the reliability of the update installation process itself.
When does support end for Windows Server 2019 and Windows 10 Enterprise LTSC 2019?
Microsoft has set the end-of-support date for both Windows Server 2019 and Windows 10 Enterprise LTSC 2019 as January 9, 2029. After that date, Microsoft will no longer provide free software updates from Windows Update, technical assistance, or security fixes for these products. Microsoft recommends upgrading to a later version of Windows Server before that deadline.
