if he didn't have the manufacturer sound drivers installed he wouldn't get any sound out of the headphones
That's not necessarily true. If he has a USB headset, then it has its own built in sound driver independent of the OS. Is this the case hassan? If so, then go to the laptop manufacturer's website and DL the specific audio drivers for your laptop model and your speakers should work.
Also, another thing that can happen is the if you plug in a secondary audio device (such as USB headphones) then Windows automatically makes it the default audio device. Go to Control Panel and then to the Audio section and look at what is the default audio output device. Its possible that the speakers will work, but the OS right now isn't sending the output to it (rather straight to the headphones). If this is the case then you'll have to toggle this, or tell whatever applications which device to use by default if you want to use both speakers & headphones.