Unless the computer is a note book computer, where it is easy to get to the lens, the only way to get to the lens in a desk top computer DVD ROM is to remove the DVD ROM from the computer and then disassemble the DVD ROM, to get to the lens. I had a Dell Dimension 4100 computer for about 6 years. All I ever used was the lens cleaner CDs with the brushes and I never had a problem with the DVD ROM. I recommend just useing the cleaning CDs with the brushes and not bother with removing and disassembling the DVD ROM unless there is a problem with the DVD ROM that a cleaning CD cannot cure.