Windows 10: 0x800f0954 when Add-WindowsCapability -Name Rsat.WSUS.Tools

On one Windows 10 workstation, when:

C:\ Add-WindowsCapability -Name Rsat.WSUS.Tools~~~~0.0.1.0 –Online 

Got:

0x800f0954

Solved it by gpedit.msc

Computer Configuration/Administrative Templates/System/Specify settings for optional component installation and component repair

Enabled it & set:

Download repair content and optional features directly from Windows Update instead of Windows Server Update Services (WSUS)

Update