Quote:

Can you use the MOVE command with variables.


Yes.

Here is a working rename script - I've commented out the "MOVE" to avoid accidents, remove the ";" when you are happy with what it is doing:
Code:
Break ON
Dim $sParent,$sEntry,$sPrefix,$sNewEntry
  
$sParent="C:\TEMP"
$sPrefix="MY_"
  
$sEntry=Dir($sParent)
While Not @ERROR
	If $sEntry<>"." AND $sEntry<>".." AND $sEntry<>"" AND (16 & GetFileAttr($sParent+"\"+$sEntry))
		$sNewEntry=$sPrefix+$sEntry
		"Renaming "+$sEntry+" -> "+$sNewEntry+": "
		If Not Exist($sParent+"\"+$sNewEntry)
			;Move $sParent+"\"+$sEntry $sParent+"\"+$sNewEntry
			If @ERROR " **FAILED with "+@ERROR+"**"+@CRLF Else "OK"+@CRLF EndIf
		Else
			" **DESTINATION ALREADY EXISTS**"+@CRLF
		EndIf
	EndIf
	$sEntry=Dir("")
Loop
  
Exit 0