change cd-rom drive letter during unattend install

To change the cdrom drive letter to say z: drive you can use the following vbs file.

' CD-ROM Change drive letter to Z:

Option Explicit

dim objShell, objFs, objDriveCollection, wshSysEnv, strTemp, strSystemRoot, intDriveLetter
Dim objDrive, objFile, strDriveType, strCMD, strVolume, strDrivesDone

Set objShell = WScript.CreateObject("WScript.Shell")
Set objfs = CreateObject("Scripting.FileSystemObject")
Set objDriveCollection = objfs.Drives

Set WshSysEnv = objShell.Environment("PROCESS")
strTemp = WshSysEnv("Temp")
strSystemRoot = WshSysEnv("SystemRoot")

intDriveLetter=90	' ascii for Z
strDrivesDone=""	' Drives that have been remapped. Prevents CDs being changed again after being moved higher up the alphabet

For Each objDrive in objDriveCollection

	Select Case objDrive.DriveType
  Case 0: strDriveType = "Unknown"
  Case 1: strDriveType = "Removable"
  Case 2: strDriveType = "Fixed"
  Case 3: strDriveType = "Network"
  Case 4: strDriveType = "CD-ROM"
  Case 5: strDriveType = "RAM Disk"
	End Select

	if strDriveType = "CD-ROM" AND instr(strDrivesDone,objDrive.DriveLetter)=0 then

  ' discover volume ID
  strCMD = strSystemroot & "\system32\cmd /c mountvol.exe " & objDrive.DriveLetter & ": /L > " & strTemp & "\volume.txt"
  objshell.run strCMD,0,true
  Set objFile = objfs.OpenTextFile(strTemp & "\volume.txt", 1)
  strVolume = ltrim(objFile.ReadLine)
  objFile.close

  ' unmount CD-ROM
  strCMD = "mountvol.exe " & objDrive.DriveLetter & ": /d"
  objShell.Run strCMD,0,true

  ' Remount CD-ROM
  strCMD = "mountvol.exe " & chr(intDriveLetter) & ": " & strVolume
  objShell.Run strCMD,0,true
  strDrivesDone=strDrivesDone & chr(intDriveLetter)
  intDriveLetter=intDriveLetter-1

	end if


Next

Copy and paste the above code and save as a .vbs file