- Download SecurityHealthSetup from: https://support.microsoft.com/en-us/topic/windows-security-update-a6ac7d2e-b1bf-44c0-a028-41720a242da3
- Right click on securityhealthsetup.exe and run as administrator. You should see a couple of command windows flash.
The Windows Security UI should work straight away. If not, restart the computer and give the system a few minutes to initialize before checking.