Check user and system path variables for duplicate entries

checkpath.ps1

# Run with administrator privileges

$RegKey = ([Microsoft.Win32.Registry]::CurrentUser).OpenSubKey("Environment", $True)
$PathValue = $RegKey.GetValue("Path", $Null, "DoNotExpandEnvironmentNames")
$RegKey.Close()
$UserPathValues = $PathValue.Split(";", [System.StringSplitOptions]::RemoveEmptyEntries)
Write-host "Current User path:`n " ($UserPathValues -join "`n  ")

$RegKey = ([Microsoft.Win32.Registry]::LocalMachine).OpenSubKey("SYSTEM\CurrentControlSet\Control\Session Manager\Environment", $True)
$PathValue = $RegKey.GetValue("Path", $Null, "DoNotExpandEnvironmentNames")
$RegKey.Close()
$SystemPathValues = $PathValue.Split(";", [System.StringSplitOptions]::RemoveEmptyEntries)
Write-host "`nCurrent System path:`n " ($SystemPathValues -join "`n  ")

$DuplicateFound = $false

$DedupUserPathValues = @()
ForEach ($Value in $UserPathValues)
{
    if ($DedupUserPathValues -notcontains $Value)
    {
        $DedupUserPathValues += $Value
    }
    else
    {
        Write-Host -ForegroundColor Yellow "Duplicate User Path entry found:" $Value
        $DuplicateFound = $true
    }
}

$DedupSystemPathValues = @()
ForEach ($Value in $SystemPathValues)
{
    if ($DedupSystemPathValues -notcontains $Value)
    {
        $DedupSystemPathValues += $Value
    }
    else
    {
        Write-Host -ForegroundColor Yellow "Duplicate System Path entry found:" $Value
        $DuplicateFound = $true
    }
}

ForEach ($Value in $DedupSystemPathValues)
{
    if ($DedupUserPathValues -contains $Value)
    {
        Write-Host -ForegroundColor Yellow "In both User and System Paths:" $Value
        $DuplicateFound = $true
    }
}

Write-Host

if (!$DuplicateFound) {
    Write-Host -ForegroundColor Green "No duplicates found"
}