How to Get System Serial Number?

This is my code but, MsgBox does not appear !
= *** even on label I can't see it {Label1.caption = strComputer & ": " & objSMBIOS.SerialNumber} )
:blush:

On Error Resume Next
Dim strComputer
strComputer = InputBox("Enter the name of the computer:")
Set objWMIService = GetObject("winmgmts:" & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
Set colSMBIOS = objWMIService.ExecQuery ("Select * from Win32_SystemEnclosure")
For Each objSMBIOS in colSMBIOS
MsgBox strComputer & ": " & objSMBIOS.SerialNumber
Next


:check:

Are you sure that your bios supports this? Not all of them do.

This works for me:

Code:

---

Option Explicit

Private Declare Function GetComputerName Lib "kernel32" Alias "GetComputerNameA" (ByVal lpBuffer As String, nSize As Long) As Long

Private Sub Command1_Click()
  Dim strComputer As String
  Dim objWMIService As Object
  Dim colSMBIOS As Object
  Dim objSMBIOS As Object
 
  strComputer = ComputerName
  On Error Resume Next
  Set objWMIService = GetObject("winmgmts:" & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
  Set colSMBIOS = objWMIService.ExecQuery("Select * from Win32_SystemEnclosure")
  For Each objSMBIOS In colSMBIOS
  MsgBox strComputer & ": " & objSMBIOS.SerialNumber
  Next
End Sub

Public Function ComputerName() As String
'Returns the computername
  Dim lngLen As Long, lngX As Long
  Dim strCompName As String
 
  lngLen = 16
  strCompName = String$(lngLen, 0)
  lngX = GetComputerName(strCompName, lngLen)
  If lngX <> 0 Then
      ComputerName = Left$(strCompName, lngLen)
  Else
      ComputerName = ""
  End If
End Function

---

For me it (objSMBIOS.SerialNumber) show nothing. Value = "None" (XP sp3, Win 7 x64, Win 10 x64 - value = "Chassis serial number").

Mahmood Khaleel Pira, what you mean 'System SN' ? SN of Operation System (Windows) ?
It is stored in this registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
Some of them is encrypted.

WMI is not meant to be used in application programs. It is an administrative service designed to be called within admin scripts used to manage PCs on LANs.

WMI is both a bit heavy and more than a little insecure. For those reasons it may be disabled or blocked by software firewalls or have its access restricted by GPO settings.


In the post-XP world we can get to the information without making kernel-level calls like WMI does though. Back in 2006 Microsoft added user-mode API calls for requesting such information directly instead of relying on values accumulated by WMI.

[VB6] Read SMBIOS info w/o WMI provides a VB6 class that wraps the API calls for convenient use. If you only need a few of the items there isn't much code required to get them:

Code:

---

Private Sub Form_Load()
    With New SmbiosInformation
        Print "SystemManufacturer: ";
        Print .Item("SystemManufacturer").Value
        Print "BaseBoardManufacturer: ";
        Print .Item("BaseBoardManufacturer").Value
        Print "BiosVendor: ";
        Print .Item("BiosVendor").Value
        Print "SystemSerialNumber: ";
        Print .Item("SystemSerialNumber").Value
    End With
End Sub

---

That code assumes AutoRedraw = True of course, but most of the time you wouldn't want this data just to display it.

The SmbiosInformation class may work on Windows XP with SP3, though that isn't guaranteed. But since Windows XP has been out of even extended support for more than two years now that shouldn't matter anyway.

Whether you use WMI or you request the information directly, if it isn't provided by the BIOS you can't get it. SystemSerialNumber is one of the values often omitted, which is why it isn't really of general use to applications anyway.