<#
   *******************************************************************************************************************************
    Name:            Reset-WindowsUpdate-WSUSManaged.ps1
    Version:         0.1.0.0 (12/02/2021)
    Purpose:         Resets Windows Update if device is managed by WSUS.
    Created by:      Ashley How
    Pre-Reqs:        PowerShell 2.0
    Version History: 0.1.0.0 - Initial Release.
   *******************************************************************************************************************************
#>

Try {
	If (-NOT (Test-Path -LiteralPath "HKLM:\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU")){ 
        Write-Output "Device is not managed by WSUS. No action required for Windows Update."
        $Check = $false
        Return

    }
	If ((Get-ItemPropertyValue -LiteralPath 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU' -Name 'UseWUServer' -ea SilentlyContinue) -eq 1) {
    } 
    Else {
        Write-Output "Device is not managed by WSUS. No action required for Windows Update."
        $Check = $false
        Return
    }
}
Catch {
    Write-Output "Device is not managed by WSUS. No action required for Windows Update."
    $Check = $false
    Return
}
$Check = $true

If ($Check -eq $true) {
    Write-Output "Device is managed by WSUS. Resetting Windows Update back to default settings..."
    
    # Get Date
    $Date = Get-Date -Format dd.MM.yyyy

    # Stop the Windows Update service
    Stop-Service -Name wuauserv

    # Remove the registry key
    Rename-Item 'HKLM:\Software\Policies\Microsoft\Windows\WindowsUpdate' -NewName 'HKLM:\Software\Policies\Microsoft\Windows\WindowsUpdate.old($date)' -Force
    Remove-Item 'HKLM:\Software\Policies\Microsoft\Windows\WindowsUpdate' -Recurse -Force

    # Start the Windows Update service
    Start-Service -Name wuauserv
}