how to update or change the printer driver using vb script

strComputer = "."
Set objWMIService = GetObject("winmgmts:" _
    & "{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
objWMIService.Security_.Privileges.AddAsString "SeLoadDriverPrivilege", True

Set colInstalledPrinters =  objWMIService.ExecQuery _
    ("Select * from Win32_Printer")

For Each objPrinter in colInstalledPrinters
        if (objPrinter.name="Oki ML 590") then
        objPrinter.driverName = "HPLaserJet4"
        objPrinter.Put_
        msgbox(objPrinter.Name)
        end if
    Wscript.Echo objPrinter.driverName
next