headphone doesnt work

hi there thanks for the response but actually she plugged it into the right socket then she also pushed properly the headset jack but still didnt work, the sound still comes from the laptop. Y_Y

I have often found that 2.5mm jacks vary somewhat and don't always fit the sockets properly. It is also sometimes quite difficult to distinguish between the three sockets, though some are colour coded to match the very thin line of insulation on the jack. I would first double check to see if she really did put the right jack in the right socket (people will swear blind that they have and when you look, they have NOT! ... I KNOW because I have done it myself.) If you really have the correct plugs in the correct sockets, try easing the plug slightly out from 'fully home'. Some jack plugs are about half a millimeter longer than they need to be and, if pushed fully home, do not make the proper connection. If it still doesn't work, then there is most likely a fault with the laptop and while another headset with a different make of plug may work, it is possible that nothing will.