Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) _
        Handles Button1.Click
 
        TextBox1.Text = WindowsCDKey()
 
    End Sub
 
    Private Function WindowsCDKey() As String
        Dim BaseKey As RegistryKey
        Dim SubKey As RegistryKey
 
        If Environment.Is64BitOperatingSystem = True Then
            BaseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, _
              RegistryView.Registry64)
            SubKey = BaseKey.OpenSubKey("SOFTWARE\Microsoft\Windows" & _
            "NT\CurrentVersion", False)
        Else
            SubKey = Registry.LocalMachine.OpenSubKey( _
              "SOFTWARE\Microsoft\Windows NT\CurrentVersion", False)
        End If
 
        Dim rpk As Byte() = DirectCast(SubKey.GetValue("DigitalProductId", New _
          Byte(-1) {}), Byte())
 
        Dim strKey As String = ""
 
        Const iRPKOffset As Integer = 52
        Const strPossibleChars As String = "BCDFGHJKMPQRTVWXY2346789"
        Dim i As Integer = 28
 
        Do
            Dim lAccu As Long = 0
            Dim j As Integer = 14
 
            Do
 
                lAccu *= 256
 
                lAccu += Convert.ToInt64(rpk(iRPKOffset + j))
 
                rpk(iRPKOffset + j) = Convert.ToByte(Convert.ToInt64(Math.Floor( _
                  CSng(lAccu) / 24.0F)) And Convert.ToInt64(255))
 
                lAccu = lAccu Mod 24
 
                j -= 1
            Loop While j >= 0
 
            i -= 1
            strKey = strPossibleChars(CInt(lAccu)).ToString() & strKey
 
            If (0 = ((29 - i) Mod 6)) AndAlso (-1 <> i) Then
                i -= 1
 
                strKey = "-" & strKey
            End If
        Loop While i >= 0
 
        Return strKey
 
    End Function