You must use a NULL Modem cable with same connection ends as the original one.

>Hello All,
>My client is using an epson printer TM-U950 receipt printer which came with a 25
>
>pin male - 9pin female cable. This printed fine. connected to Com1.
>The cable got lost and was replaced with a 25 pin male - 25 pin male cable serial cable (usual ones on the market). I connected it to the printer port.
>Unfortunately it cannot print well. just ??????. which denotes 'Receive error'
>Do i need a special cable or it is possible to change the wiring strucure or some settings.
>Please advise.
>
>
>TIA