Public Class Form1
    Inherits System.Windows.Forms.Form
 
#Region " Vom Windows Form Designer generierter Code "
 
    Public Declare Function GetVolumeInformation Lib "kernel32.dll" _
        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 Structure SerialInfo
        Public drivenumber As String
        Public serialnumber As String
    End Structure
 
    Public Function Lowbyte(ByRef ptradress As Integer) As Integer
        Return ptradress And &HFFFF
    End Function
 
    Public Function Highbyte(ByRef ptradress As Integer) As Integer
        If (ptradress And &H80000000) = &H80000000 Then
            Return ((ptradress And &H7FFF0000) \ &H10000) Or &H8000&
        Else
            Return (ptradress And &HFFFF0000) \ &H10000
        End If
    End Function
 
    Public Function EnumSerialNumber(ByVal lpRootPathName As String) As _
      SerialInfo
        Dim lpVolumeNameBuffer As New String(" ", 255)
        Dim lpVolumeSerialNumber As Integer
        Dim lpMaximumComponentLength As Integer
        Dim lpFileSystemFlags As Integer
        Dim lpFileSystemNameBuffer As New String(" ", 255)
        Dim si As New SerialInfo
 
        GetVolumeInformation(lpRootPathName, _
              lpVolumeNameBuffer, _
              lpVolumeNameBuffer.Length, _
              lpVolumeSerialNumber, _
              lpMaximumComponentLength, _
              lpFileSystemFlags, _
              lpFileSystemNameBuffer, _
              Len(lpFileSystemNameBuffer))
 
        Try
            si.drivenumber = lpRootPathName
            Dim lw As Integer = Lowbyte(lpVolumeSerialNumber)
            Dim hw As Integer = Highbyte(lpVolumeSerialNumber)
            si.serialnumber = Hex(hw).PadLeft(4, "0") & "-" & Hex(lw).PadLeft( _
              4, "0")
            Return si
        Catch ex As Exception
        End Try
    End Function
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Me.TextBox1.Text = EnumSerialNumber("C:").serialnumber
    End Sub
End Class

Das Meiste wird deshalb nicht getan, weil es nicht unternommen wird.