A script to fetch Windows key from system

windows-key-retrieval-script.ps1

# Function to retrieve the product key from the registry
function Get-WindowsKey {
    try {
        $path = 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SoftwareProtectionPlatform'
        $key = (Get-ItemProperty -Path $path -Name BackupProductKeyDefault -ErrorAction Stop).BackupProductKeyDefault
        return $key
    } catch {
        return $null
    }
}

# Function to get the key using WMI
function Get-WindowsKeyWMI {
    try {
        $key = (Get-WmiObject -query 'select * from SoftwareLicensingService').OA3xOriginalProductKey
        return $key
    } catch {
        return $null
    }
}

# Function to decode the binary key
function ConvertTo-Key($Key) {
    $keyOffset = 52
    $isWin8 = [int]($Key[66] / 6) -band 1
    $HexDigits = "BCDFGHJKMPQRTVWXY2346789"
    $i = 24
    [string]$result = ""

    # Decoding the key
    while ($i -ge 0) {
        $r = 0
        for ($j = 14; $j -ge 0; $j--) {
            $r = ($r * 256) -bxor $Key[$j + $keyOffset]
        }
        for ($j = 24; $j -ge 0; $j -= 4) {
            $result = $HexDigits[$r -band 0x0f] + $result
            $r = $r -shr 4
        }
        $i--
    }

    if ($isWin8 -eq 1) {
        $result = $result.Substring(1)
        $result = $result.Insert(0, "N")
    }

    return $result.Insert(5, "-").Insert(11, "-").Insert(17, "-").Insert(23, "-")
}

# Main script
$registryKey = Get-WindowsKey
$wmiKey = Get-WindowsKeyWMI

Write-Host "Attempting to retrieve Windows product key..."

if ($registryKey) {
    Write-Host "Product Key (from Registry): $registryKey"
} elseif ($wmiKey) {
    Write-Host "Product Key (from WMI): $wmiKey"
} else {
    Write-Host "Unable to retrieve product key using standard methods. Attempting advanced method..."
    try {
        $map = "BCDFGHJKMPQRTVWXY2346789"
        $value = (Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion").DigitalProductId[0x34..0x42]
        $productKey = ConvertTo-Key $value
        Write-Host "Product Key (Decoded): $productKey"
    } catch {
        Write-Host "Error: Unable to retrieve or decode product key."
    }
}

# Display license information
$license = Get-CimInstance -ClassName SoftwareLicensingProduct | Where-Object { $_.PartialProductKey } | Select-Object Description, LicenseStatus
Write-Host "`nLicense Information:"
Write-Host "Description: $($license.Description)"
Write-Host "Status: $($license.LicenseStatus)"