The Windows Subsystem for Linux optional component is not enabled.

C++
Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux
Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linuxdism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestartdism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart
dism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestart

Source

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