How to find hard disk serial number ?

How to find hard disk serial number ?

If you want to get the hard drive serial number or computer unique number then use this function.
This is Visual Basic 6.0 Code to Get the Computer Hard Drive Serial Number.

‘Computer Unique No or hard drive serial number From Visual Basic

Private Declare Function GetVolumeInformation _
Lib "kernel32.dll" _
Alias "GetVolumeInformationA" _
(ByVal lpRootPathName As String, _
ByVal lpVolumeNameBuffer As String, _
ByVal nVolumeNameSize As Integer, _
lpVolumeSerialNumber As Long, _
lpMaximumComponentLength As Long, _
lpFileSystemFlags As Long, _
ByVal lpFileSystemNameBuffer As String, _
ByVal nFileSystemNameSize As Long) As Long

This Function will return serial number of a Drive

Public Function GetSerialNumber(DriveLetter As String) As String
Dim SerialNum As Long
Dim VolNameBuf As String
Dim FileSysNameBuf As String

Select Case Len(DriveLetter)
Case 1
If DriveLetter Like "[a-z]" Then
DriveLetter = Left$(DriveLetter, 1) & ":\"
Else
GetSerialNumber = "Error - Bad drive designation"
End If
Case 2
If LCase(DriveLetter) Like "[a-z]:" Then
DriveLetter = DriveLetter & "\"
Else
GetSerialNumber = "Error - Bad drive designation"
End If
Case 3
If LCase(DriveLetter) Like "[!a-z]:\" Then
GetSerialNumber = "Error - Bad drive designation"
End If
Case Else
GetSerialNumber = "Error - Bad drive designation"
End Select
If Len(GetSerialNumber) = 0 Then
VolNameBuf = String$(255, Chr$(0))
FileSysNameBuf = String$(255, Chr$(0))
GetVolumeInformation DriveLetter, VolNameBuf, _
Len(VolNameBuf), SerialNum, 0, 0, _
FileSysNameBuf, Len(FileSysNameBuf)
GetSerialNumber = Right$("00000000" & Hex$(SerialNum), 8)
End If
End Function

This is good for security purpose. some time if you want to run your EXE file on some computer only then this is the best way.