Const OFS_MAXPATHNAME = 128
Const OF_CREATE = &H1000
Const OF_READ = &H0
Const OF_WRITE = &H1

Private Type FILETIME
        dwLowDateTime As Long
        dwHighDateTime As Long
End Type
 
Private Type BY_HANDLE_FILE_INFORMATION
        dwFileAttributes As Long
        ftCreationTime As FILETIME
        ftLastAccessTime As FILETIME
        ftLastWriteTime As FILETIME
        dwVolumeSerialNumber As Long
        nFileSizeHigh As Long
        nFileSizeLow As Long
        nNumberOfLinks As Long
        nFileIndexHigh As Long
        nFileIndexLow As Long
End Type

Private Type OFSTRUCT
        cBytes As Byte
        fFixedDisk As Byte
        nErrCode As Integer
        Reserved1 As Integer
        Reserved2 As Integer
        szPathName(OFS_MAXPATHNAME) As Byte
End Type

Private Declare Function GetFileInformationByHandle Lib "kernel32" (ByVal hFile As Long, lpFileInformation As BY_HANDLE_FILE_INFORMATION) As Long
Private Declare Function OpenFile Lib "kernel32" (ByVal lpFileName As String, lpReOpenBuff As OFSTRUCT, ByVal wStyle As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long

Function GetFileIdentifier(strFilePath) As String

Dim lngFileHandle As Long
Dim FileInfo As BY_HANDLE_FILE_INFORMATION
Dim OF As OFSTRUCT

lngFileHandle = OpenFile(strFilePath, OF, OF_READ)

GetFileInformationByHandle lngFileHandle, FileInfo

CloseHandle lngFileHandle

GetFileIdentifier = CStr(FileInfo.nFileIndexHigh) & CStr(FileInfo.nFileIndexLow)
    
End Function