dell webcam central

i have mini10v inspiron and it has a built in webcam and it uses a dell webcam central then suddenly one time i need to use my webcam then it says "please plug in a support webcam" i already tried to uninstall the webcam central driver and install it again but still no webcam to detect. how come i lost my webcam when in fact it is an built in webcam right? so can someone help me please about this issue , is this a hardware issue? do i need it to return it bec. it is still under warranty? thanks..