Assuming you have the mic plug connected properly to the mic jack on the PC, go to the Control Panel/Hardware and Sound and finally the Sound Panel. click the Recording tab. The mic should show as connected, right click on the mic icon and then LEFT click Properties. One of the tabs in that panel will be to set the mic level, move the slider up to 100 and see if works. Also, if you have the System Mixer, make sure its set as the Default recording device.