Question:
I want to get the serial number from my hard drive and my floppy disk drive. How can I do this?

Answer:
The GetVolumeInformation API call is used to retrieve information about hard drives, floppy drives, and even CD-ROM drives. Notice how your Windows CD player can recognize which CD is inserted? It is using the serial number of the CD-ROM (obtained with this API call) to make this determination. Just substitute the drive letter where it currently says “F:” and you can check on any of your drives.

The code that follows will return the serial number (as a long), as well as the volume name and volume type, such as FAT. However, the text in the returned strings is ended with a null character – chr$(0). That’s the reason for the InStr call — it only shows the portion of the string up to the null character. If you don’t do that, the DLL showing the MsgBox interprets the null character as the end of line and no further text is displayed.

Option ExplicitPrivate Declare Function GetVolumeInformation _   Lib “kernel32” Alias “GetVolumeInformationA” _   (ByVal lpRootPathName As String, _   ByVal lpVolumeNameBuffer As String, _   ByVal nVolumeNameSize As Long, _   lpVolumeSerialNumber As Long, _   lpMaximumComponentLength As Long, _   lpFileSystemFlags As Long, _   ByVal lpFileSystemNameBuffer As String, _   ByVal nFileSystemNameSize As Long) As Long   Private Sub cmdTest_Click()   Dim iSerialNum As Long   Dim sVolumeLabel As String   Dim sVolumeType As String   Dim iRetVal As Long   sVolumeLabel = Space(255)   sVolumeType = Space(255)   iRetVal = GetVolumeInformation(“f:”, _      sVolumeLabel, Len(sVolumeLabel), _      iSerialNum, _      0, 0, _      sVolumeType, Len(sVolumeType))      MsgBox “Disk Serial Number: ” & iSerialNum & vbCrLf _      & “Volume Type: ” & Left$(sVolumeType, InStr(sVolumeType, Chr$(0)) – 1) & vbCrLf _      & “Volume Label: ” & Left$(sVolumeLabel, InStr(sVolumeLabel, Chr$(0)) – 1)End Sub