a) Type CMD in search box from Start menu
b) Right-click on Command Prompts app on the top and click Run as administrator
c) Click YES when prompted by UAC ( USER ACCOUNT CONTROL )
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2) Type the commands blow and hit Enter one by one
a) Type dism /online /cleanup-image /restorehealth and hit Enter
b) Type sfc /scannow and hit Enter
c) Type powershell and hit Enter
d) Type Get-AppXPackage -AllUsers |Where-Object {$_.InstallLocation -like “*SystemApps*”} | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml”} and hit Enter
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Now press WIN + L keys to lock screen and check. You should be able to see Windows Spotlight screen now.