Here is an example of how to do it. The findVolume() UDF will return the first drive whose title starts with the volume name passed to it.

Note, I have deliberately *not* restricted this to CD drives. This means that you can network map a dummy drive letter with the correct label for testing.

In this example the script looks for a drive with a label starting "MyDrive". If it doesn't find one it defaults to "C:"

Code:
Break ON
$=SetOption("Explicit","ON")
 
Dim $sDrive
 
$sDrive=findVolume("MyDrive")
If $sDrive="" $sDrive="C:" Endif
"Will use drive letter "+$sDrive+@CRLF
 
Function findVolume($sVolume)
	Dim $oFSO, $oDrive
 
	$findVolume=""
	$oFSO=CreateObject("Scripting.FileSystemObject")
	If Not @ERROR AND VarType($oFSO)=9
		For Each $oDrive In $oFSO.Drives
			If InStr($oDrive.VolumeName,$sVolume)=1 $findVolume=$oDrive.DriveLetter+":" Exit 0 EndIf
		Next
	EndIf
	Exit 15
EndFunction