3mm not working

[Guest]

3 years ago, I used 3mm headset but that broke. then forward I used USB. However, now with my new headset, sound is not working with 3mm I looked in playback devices and tried out every option. What should I do???

 

[Alabalcho]

Are you talking about desktop / laptop?
3.5mm output on a desktop is usually labeled green. Try the one on the back panel first. You will have then to discover which audio device corresponds to this connector, unplug all USB audio devices to eliminate them.
Make sure your headphones work as well - plug them into a phone / tablet to confirm.