ขอความช่วยเหลือนิดนึงครับเกี่ยวกับการหา Serial Harddisk

Public Class Form1

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim svn As String
        Dim have_file = My.Computer.FileSystem.GetFileInfo("C:\WINDOWS\system32\sn.ini")

        svn = LwSerialNumber("C:\")
        If have_file.Exists Then
            My.Computer.FileSystem.DeleteFile("C:\WINDOWS\system32\sn.ini")

        End If
        My.Computer.FileSystem.WriteAllText("C:\WINDOWS\system32\sn.ini", svn, False)


    End Sub
    Declare Function GetVolumeInformation Lib "kernel32" Alias "GetVolumeInformationA" (ByVal lpRootPathName As String, ByVal lpVolumeNameBuffer As String, ByVal nVolumeNameSize As Integer, ByRef lpVolumeSerialNumber As Integer, ByRef lpMaximumComponentLength As Integer, ByRef lpFileSystemFlags As Integer, ByVal lpFileSystemNameBuffer As String, ByVal nFileSystemNameSize As Integer) As Integer

    Public Function LwSerialNumber(ByVal Lw As String) As String
        Dim FileSystem As String
        Dim SerNum As Long
        Dim MaxLen As Long
        Dim Flags As Long
        Dim VolSize As Long
        Dim VolLabel As String
        Dim SerialNumber As String

        FileSystem = Space(256)
        If GetVolumeInformation(Lw, VolLabel, VolSize, SerNum, MaxLen, Flags, FileSystem, Len(FileSystem)) <> 0 Then


            SerialNumber = Trim(Hex(SerNum))
            SerialNumber = Microsoft.VisualBasic.Strings.Left(SerialNumber, 4) & "-" & Microsoft.VisualBasic.Strings.Right(SerialNumber, 4)

            LwSerialNumber = SerialNumber
        Else
            LwSerialNumber = "Invalid Drive"
        End If
    End Function

    
End Class

Dim VolLabel As String =""