On March 3, 2026, Microsoft took a significant step by re-releasing update KB5075039, aimed at restoring functionality to the Windows Recovery Environment (WinRE) for Windows 10. This update is particularly relevant for users of Windows 10, which officially fell out of support in October 2025.
The backdrop to this update involves a bug that emerged with the installation of dynamic security update KB5067039. This update, rolled out in October 2025, introduced a problematic version of the USBHUB3.SYS driver, specifically version 10.0.26100.6891. As a consequence, users found themselves unable to utilize USB keyboards and mice within the WinRE, a critical environment for troubleshooting and recovery. Microsoft acknowledged this issue on October 17, 2025, prompting discussions in various forums, including a detailed blog post addressing the malfunction.
In mid-January 2026, Microsoft released new recovery updates for both Windows 10 and Windows 11. Notably, update KB5075039 was distributed on January 15, 2026, targeting Windows 10 versions 21H2 and 22H2. This update was designed to automatically apply the Safe OS Dynamic Update (KB5073933) to the WinRE of active PCs. However, it appears that this initial attempt did not resolve the underlying issue.
Windows 10 update KB5073933 (March 3, 2026)
It was with some surprise that the tech community noted the re-release of update KB5073933 for Windows 10 versions 21H2 and 22H2 ESU, as well as Windows 10 Enterprise LTSC 2021, on March 3, 2026. According to Microsoft’s support documentation, this update addresses a critical bug that prevents the WinRE from starting altogether when the previous WinRE update, KB5068164, is installed.
For users operating Windows 10 22H2 with ESU support, the installation of the KB5073933 update is highly recommended to ensure a functional recovery environment. This proactive measure underscores Microsoft’s commitment to maintaining support for its users, even as the official support timeline for Windows 10 has lapsed.
