Public Function FlashSerials() As String
    Dim cad As String
   Dim TGUID As GUID 
 
   Call IIDFromString(StrPtr("{53f56307-b6bf-11d0-94f2-00a0c91efb8b}"), TGUID)
 
   Dim hDev As Long
   ' puntero a la clase de los USB
   hDev = SetupDiGetClassDevs(TGUID, &H0, &H0, &H12)
 
   If hDev = -1 Then Exit Function
 
   Dim lCount       As Long
   Dim lSize        As Long
   Dim DTL          As SP_DEVICE_INTERFACE_DETAIL_DATA
   Dim DTA          As SP_DEVICE_INTERFACE_DATA
 
   DTA.cbSize = Len(DTA)
   DTL.cbSize = &H5
   lCount = &H0
 
   While Not (SetupDiEnumDeviceInterfaces(hDev, &H0, TGUID, lCount, DTA) = &H0)
 
     Call SetupDiGetDeviceInterfaceDetail(hDev, DTA, ByVal &H0, &H0, lSize, ByVal &H0)
 
     Call SetupDiGetDeviceInterfaceDetail(hDev, DTA, DTL, ByVal lSize, lSize, ByVal &H0)
 
     If UBound(Split(DTL.strDevicePath, "#")) > 1 Then
        cad = cad & Split(UCase$(DTL.strDevicePath), "#")(1) & _
         " - " & Split(UCase$(DTL.strDevicePath), "#")(2) & Chr$(&HD)
        'cad = cad & DTL.strDevicePath & Chr(10)
     End If
 
     lCount = lCount + 1
   Wend
 
   Call SetupDiDestroyDeviceInfoList(hDev)
   FlashSerials = cad
   If FlashSerials = "" Then FlashSerials = "No hay conexiones"
 
End Function
 

estas seguro que no es el serial verdadero?  

 
Option Explicit
 
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Function: SerialHD
' Autor: Adrian Desanti (Dessa)
' Creditos: es una adaptacion a mis necesidades de una clase de Antonio Giuliana
' Agradecimientos: Karcrak (IsAdministrador)
' Requisitos : Windows NT + Administrador
' Rertorno: retorna el serial verdadero de Discos IDE o S-ATA conectados
' Serial verdadero: Es el que figura en la etiqueta del Disco y no cambia al formatear
' Fecha : V.2 Septiembre 2010
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 
Private Declare Function CheckTokenMembership Lib "ADVAPI32" (ByVal TokenHandle As Long, ByVal pSidToCheck As Long, ByRef IsMember As Boolean) As Long
 
Private Declare Function GetVersion Lib "KERNEL32" () As Long
Private Declare Function CreateFile Lib "KERNEL32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As Long, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function CloseHandle Lib "KERNEL32" (ByVal hObject As Long) As Long
Private Declare Function DeviceIoControl Lib "KERNEL32" (ByVal hDevice As Long, ByVal dwIoControlCode As Long, lpInBuffer As Any, ByVal nInBufferSize As Long, lpOutBuffer As Any, ByVal nOutBufferSize As Long, lpBytesReturned As Long, ByVal lpOverlapped As Long) As Long
Private Declare Sub ZeroMemory Lib "KERNEL32" Alias "RtlZeroMemory" (dest As Any, ByVal numBytes As Long)
 
Private Type IDEREGS
    bFeaturesReg As Byte: bSectorCountReg As Byte: bSectorNumberReg As Byte: bCylLowReg As Byte: bCylHighReg As Byte: bDriveHeadReg As Byte: bCommandReg As Byte: bReserved As Byte
End Type
Private Type SENDCMDINPARAMS
    cBufferSize As Long: irDriveRegs As IDEREGS: bDriveNumber As Byte: bReserved(1 To 3) As Byte: dwReserved(1 To 4) As Long
End Type
Private Type DRIVERSTATUS
    bDriveError As Byte: bIDEStatus As Byte: bReserved(1 To 2) As Byte: dwReserved(1 To 2) As Long
End Type
Private Type SENDCMDOUTPARAMS
    cBufferSize As Long: DStatus As DRIVERSTATUS: bBuffer(1 To 512) As Byte
End Type
 
Private Declare Function IIDFromString Lib "ole32" (ByVal lpsz As Long, ByRef lpiid As GUID) As Long
Private Declare Function SetupDiGetClassDevs Lib "setupapi.dll" Alias "SetupDiGetClassDevsA" (ByVal ClassGuid As Long, ByVal Enumerator As Long, ByVal HwndParent As Long, ByVal flags As Long) As Long
Private Declare Function SetupDiEnumDeviceInterfaces Lib "setupapi.dll" (ByVal DeviceInfoSet As Long, ByVal DeviceInfoData As Long, ByRef InterfaceClassGuid As GUID, ByVal MemberIndex As Long, ByRef DeviceInterfaceData As SP_DEVICE_INTERFACE_DATA) As Long
Private Declare Function SetupDiDestroyDeviceInfoList Lib "setupapi.dll" (ByVal DeviceInfoSet As Long) As Long
 
Private Type GUID
    Data1 As Long: Data2 As Integer: Data3 As Integer: Data4(0 To 7) As Byte
End Type
 
Private Type SP_DEVICE_INTERFACE_DATA
    cbSize As Long: InterfaceClassGuid As GUID: flags As Long: Reserved As Long
End Type
 
 
Private Sub Form_Load()
 
  If (GetVersion And &HFF) > &H5 Then
    If App.LogMode = 0 Then
        MsgBox "En Vista o Seven ejecutar compilado en modo Administrador"
        End
    End If
  End If
 
 
  AutoRedraw = True
  FontBold = True
  Caption = ""
  Print SerialHD()
 
 
 
End Sub
 
Public Function SerialHD() As String
 
  If (GetVersion And &HFF) < 5 Then
    SerialHD = "Sistema Operativo No válido"
    Exit Function
  End If
 
  If IsAdministrador = False Then
    SerialHD = "Se requiere usuario Administrador"
    Exit Function
  End If
 
  Dim RetDiskCount  As Long
 
  RetDiskCount = DiskCount()
 
  If RetDiskCount < 0 Then
    SerialHD = "DiskCount No válido"
    Exit Function
  End If
 
  Dim nDisco        As Long
  Dim hdh           As Long
  Dim hddfr         As Byte
  Dim hddln         As Byte
  Dim bin           As SENDCMDINPARAMS
  Dim bout          As SENDCMDOUTPARAMS
  Dim br            As Long
  Dim x             As Byte
  Dim s             As String
 
  For nDisco = 0 To RetDiskCount - 1 ' los ciclos del For serán solo la cantidad de "PhysicalDrive" conectados
 
      hdh = CreateFile("\\.\PhysicalDrive" & nDisco, &H3, &H0, &H0, &H3, &H0, &H0)
 
      If hdh = -1 Then
          If nDisco = 0 Then
              SerialHD = " IDE " & nDisco & " = " & "Error en CreateFile" & vbNewLine
          Else
              SerialHD = SerialHD & " IDE " & nDisco & " = " & "Error en CreateFile" & vbNewLine
          End If
      Else
          hddfr = 21 ' Posicion en el buffer del SerialNumber
          hddln = 20 ' Tamaño resrvado en el buffer para el SerialNumber
 
          Call ZeroMemory(bin, Len(bin))
          Call ZeroMemory(bout, Len(bout))
 
          With bin
              .bDriveNumber = nDisco
              .cBufferSize = 512
            With .irDriveRegs
                If (nDisco And 1) Then
                    .bDriveHeadReg = &HB0
                Else
                    .bDriveHeadReg = &HA0
                End If
                .bCommandReg = &HEC
                .bSectorCountReg = 1
                .bSectorNumberReg = 1
            End With
          End With
 
          'DFP_RECEIVE_DRIVE_DATA = &H7C088
          Call DeviceIoControl(hdh, &H7C088, bin, Len(bin), bout, Len(bout), br, 0)
 
          s = ""
          For x = hddfr To hddfr + hddln - 1 Step 2
              If bout.bBuffer(x + 1) = 0 Then Exit For
              s = s & Chr(bout.bBuffer(x + 1))
              If bout.bBuffer(x) = 0 Then Exit For
              s = s & Chr(bout.bBuffer(x))
          Next x
          Call CloseHandle(hdh)
 
          If Trim$(s) <> "" Then
              SerialHD = SerialHD & " IDE " & nDisco & " = " & Trim$(s) & vbNewLine
          End If
      End If
 
  Next nDisco
 
End Function
 
Private Function DiskCount() As Long
 
    Dim TGUID   As GUID
    Dim hDev    As Long
 
    Call IIDFromString(StrPtr("{53f56307-b6bf-11d0-94f2-00a0c91efb8b}"), TGUID)
 
    '&H12 ===> DIGCF_PRESENT = &H10 Or DIGCF_DEVICEINTERFACE = &H2
    hDev = SetupDiGetClassDevs(VarPtr(TGUID), &H0, &H0, &H12)
 
    If hDev = -1 Then
      DiskCount = -1
      Exit Function
    End If
 
    Dim Cnt As Long
    Dim DTA  As SP_DEVICE_INTERFACE_DATA
    DTA.cbSize = Len(DTA)
 
    While Not (SetupDiEnumDeviceInterfaces(hDev, &H0, TGUID, Cnt, DTA) = &H0)
        Cnt = Cnt + 1
    Wend
 
    Call SetupDiDestroyDeviceInfoList(hDev)
 
    DiskCount = Cnt
 
End Function
 
Private Function IsAdministrador() As Boolean
   Dim SID(1)  As Currency
   SID(0) = 36028797018964.0193@
   SID(1) = 233646220.9056@
   Call CheckTokenMembership(&H0, VarPtr(SID(0)), IsAdministrador)
End Function