Windows 11, boinc registry cleanup of orphaned installations remaining in "Add or remove programs"

clear_boinc.ps1

[CmdletBinding()]
param()

$identity = [Security.Principal.WindowsIdentity]::GetCurrent()
$principal = New-Object Security.Principal.WindowsPrincipal($identity)
$adminRole = [Security.Principal.WindowsBuiltInRole]::Administrator

if (-not $principal.IsInRole($adminRole)) {
    Start-Process powershell.exe -ArgumentList "-NoExit -NoProfile -ExecutionPolicy Bypass -File `"$PSCommandPath`"" -Verb RunAs
    exit
}

$hives = @(
    "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKCU:\Software\Microsoft\Windows\CurrentVersion\Uninstall\*",
    "HKLM:\SOFTWARE\Classes\Installer\Products\*"
)

$found = @()

foreach ($path in $hives) {
    $keys = Get-Item -Path $path -ErrorAction SilentlyContinue
    foreach ($key in $keys) {
        $props = Get-ItemProperty -Path $key.PSPath -ErrorAction SilentlyContinue
        
        $displayName = [string]$props.DisplayName
        $productName = [string]$props.ProductName
        $keyName = [string]$key.Name
        $installDir = [string]$props.InstallLocation

        $isMatch = ($displayName -match "BOINC") -or ($productName -match "BOINC") -or ($keyName -match "BOINC")
        if (-not $isMatch) { continue }

        $dirStatus = "Purged (Folder Missing)"
        if ([string]::IsNullOrWhiteSpace($installDir)) { 
            $dirStatus = "Never Existed (No Path in Registry)"
            $installDir = "N/A"
        }

        $pathValid = $installDir -ne "N/A" -and (Test-Path $installDir)
        if ($pathValid) { $dirStatus = "Exists (Skipping)" }

        $found += [PSCustomObject]@{
            EntryName    = $displayName ? $displayName : ($productName ? $productName : $key.PSChildName)
            DirStatus    = $dirStatus
            InstallDir   = $installDir
            RegistryPath = $key.PSPath
        }
    }
}

$results = $found | Sort-Object RegistryPath -Unique

if ($results.Count -eq 0) {
    Write-Output "No BOINC entries found."
    return
}

$skipped = $results | Where-Object { $_.DirStatus -eq "Exists (Skipping)" }
if ($skipped.Count -gt 0) {
    Write-Output "`n--- SKIPPED (Installation Directory Still Exists) ---"
    $skipped | Format-Table EntryName, DirStatus, InstallDir, RegistryPath -AutoSize -Wrap
}

$orphaned = $results | Where-Object { $_.DirStatus -ne "Exists (Skipping)" }
if ($orphaned.Count -eq 0) {
    Write-Output "`nNo orphaned entries available for removal."
    return
}

Write-Output "`n--- READY FOR REMOVAL ---"
$orphaned | Format-Table EntryName, DirStatus, InstallDir, RegistryPath -AutoSize -Wrap

$confirmation = Read-Host "Delete these $($orphaned.Count) orphaned registry entries? (Y/N)"
if ($confirmation -notmatch "^[yY]$") { 
    Write-Output "Operation cancelled."
    return 
}

foreach ($item in $orphaned) {
    Remove-Item -Path $item.RegistryPath -Recurse -Force -ErrorAction SilentlyContinue
    Write-Output "Removed: $($item.RegistryPath)"
}

Write-Output "Cleanup complete."