Problems getting headphones w/ mic to work

Hi all. i have a headset with mic with usb connection. they dont seem to work on the headphone part. im told i can be heard when talkin so im assuming the mic part is ok. i took the headphones and plugged them into my moms laptop and both components work properly on hers. she has the same headet i do and hers dont wrok on mine either. so any help would be apreciated.

Does it ONLY have a USB connection or does it have USB plus 1/8" stereo jacks? Sometimes they have both and then the USB is just for power.

If it is truly a USB device then I would try going to Control panel > Sound.
If it is USB then it should show up in the list of playback devices.
I would check the properties and if available try the configure button.