How to Manually Update Microsoft Defender on Windows 10 11 (GUI . . . Microsoft documents Defender’s update flow through its antimalware tooling, and the common manual commands used by administrators are Update-MpSignature and the Defender command-line utility MpCmdRun exe with the signature-update switch
How to Update Windows Security Signatures Manually Windows 11 10 To manually update your Windows Security signatures, right-click on the Start button, click Settings, click Update Security (if Windows 11, click Privacy Security), select Windows Security, click Virus Threat Protection, click Check for Updates, wait until Windows installs the available updates, and then restart your computer