Get-ItemPropertyValue "HKLM:SOFTWARE\Microsoft\Windows NT\CurrentVersion" -Name CurrentBuildNumber
# Expected: 22621

Or via winver – Build 22621.2428

While the specific details of each fix and feature might be extensive, cumulative updates generally include:

The x64 version contains a digitally signed binary ntoskrnl.exe with checksum different from the x86 emulation layer on Arm64. Do not attempt to cross-deploy.

| Issue | Affects | Workaround | |-------|---------|-------------| | BitLocker recovery prompt after update on self-encrypting drives | Some NVMe SSDs (e.g., SK Hynix, certain Samsung) | Pause updates if BitLocker is critical. After update, enter recovery key from Azure AD/AD. | | Copilot icon missing even after update | Enterprise with GPO “Turn off Copilot” | Enable via Computer Configuration\Administrative Templates\Windows Components\Windows Copilot | | File Explorer context menu slow (1‑2 sec delay) | Users with many cloud files (OneDrive/Box) | Workaround: reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Shell Extensions\Blocked" /v "e2bf9676-5f8f-435c-97eb-11607a5bedf7" /t REG_SZ | | Sysprep fails with 0x80073CFA | Custom images with UWP apps | Remove provisioned packages before sysprep, or capture after update without sysprep. |

KB5031358 is a mandatory, cumulative update that includes all previous improvements from September 2023 (KB5030319) plus new security and non-security fixes. It is not available for Windows 11 version 21H2 (which reached end of support on October 10, 2023).