acer laptop dont have sound

[manauwer_ali]

no speaker or headphone plugged in

 

[Grobe]

This sound very simple, but I have done it myself - do your laptop have a physically slider (volume up/down) somewhere? Are the sound muted by software?

 

[Alabalcho]

Do you have audio device in "Device manager"? Do you have "Volume Control"? What is default "Playback device"?
Are you sure your headphones work - have you tried them on eg a smartphone?