#Main function
Function GetWin10Key
{
    $Hklm = 2147483650
    $Target = $env:COMPUTERNAME
    $regPath = "Software\Microsoft\Windows NT\CurrentVersion"
    $DigitalID = "DigitalProductId"
    $wmi = [WMIClass]"\\$Target\root\default:stdRegProv"
    #Get registry value
    $Object = $wmi.GetBinaryValue($hklm,$regPath,$DigitalID)
    [Array]$DigitalIDvalue = $Object.uValue
    #If get successed
    If($DigitalIDvalue)
    {
        #Get producnt name and product ID
        $ProductName = (Get-itemproperty -Path "HKLM:Software\Microsoft\Windows NT\CurrentVersion" -Name "ProductName").ProductName
        $ProductID =  (Get-itemproperty -Path "HKLM:Software\Microsoft\Windows NT\CurrentVersion" -Name "ProductId").ProductId
        #Convert binary value to serial number
        $Result = ConvertTokey $DigitalIDvalue
        $OSInfo = (Get-WmiObject "Win32_OperatingSystem"  | select Caption).Caption
        If($OSInfo -match "Windows 10")
        {
            if($Result)
            {

                [string]$value ="ProductName  : $ProductName `r`n" `
                + "ProductID    : $ProductID `r`n" `
                + "Installed Key: $Result"
                $value
                #Save Windows info to a file
                $Choice = GetChoice
                If( $Choice -eq 0 )
                {
                    $txtpath = "C:\Users\"+$env:USERNAME+"\Desktop"
                    New-Item -Path $txtpath -Name "WindowsKeyInfo.txt" -Value $value   -ItemType File  -Force | Out-Null
                }
                Elseif($Choice -eq 1)
                {
                    Exit
                }
            }
            Else
            {
                Write-Warning "Запускайте скрипт в Windows 10"
            }
        }
        Else
        {
            Write-Warning "Запускайте скрипт в Windows 10"
        }

    }
    Else
    {
        Write-Warning "Возникла ошибка, не удалось получить ключ"
    }

}
#Get user choice
Function GetChoice
{
    $yes = New-Object System.Management.Automation.Host.ChoiceDescription "&Yes",""
    $no = New-Object System.Management.Automation.Host.ChoiceDescription "&No",""
    $choices = [System.Management.Automation.Host.ChoiceDescription[]]($yes,$no)
    $caption = "Подтверждение"
    $message = "Сохранить ключ в текстовый файл?"
    $result = $Host.UI.PromptForChoice($caption,$message,$choices,0)
    $result
}
#Convert binary to serial number
Function ConvertToKey($Key)
{
    $Keyoffset = 52
    $isWin10 = [int]($Key[66]/6) -band 1
    $HF7 = 0xF7
    $Key[66] = ($Key[66] -band $HF7) -bOr (($isWin10 -band 2) * 4)
    $i = 24
    [String]$Chars = "BCDFGHJKMPQRTVWXY2346789"
    do
    {
        $Cur = 0
        $X = 14
        Do
        {
            $Cur = $Cur * 256
            $Cur = $Key[$X + $Keyoffset] + $Cur
            $Key[$X + $Keyoffset] = [math]::Floor([double]($Cur/24))
            $Cur = $Cur % 24
            $X = $X - 1
        }while($X -ge 0)
        $i = $i- 1
        $KeyOutput = $Chars.SubString($Cur,1) + $KeyOutput
        $last = $Cur
    }while($i -ge 0)

    $Keypart1 = $KeyOutput.SubString(1,$last)
    $Keypart2 = $KeyOutput.Substring(1,$KeyOutput.length-1)
    if($last -eq 0 )
    {
        $KeyOutput = "N" + $Keypart2
    }
    else
    {
        $KeyOutput = $Keypart2.Insert($Keypart2.IndexOf($Keypart1)+$Keypart1.length,"N")
    }
    $a = $KeyOutput.Substring(0,5)
    $b = $KeyOutput.substring(5,5)
    $c = $KeyOutput.substring(10,5)
    $d = $KeyOutput.substring(15,5)
    $e = $KeyOutput.substring(20,5)
    $keyproduct = $a + "-" + $b + "-"+ $c + "-"+ $d + "-"+ $e
    $keyproduct


}
GetWin10Key