Built In Camera On Oovoo Built In Webcam Help For HP Pavilion Enternainment Lap Top?

Built in webcam help for HP Pavilion enternainment Lap top? - built in camera on oovoo

My camera has always worked and suddenly I began with my camera yesterday and ooVoo worked, but now the usual work, and when I say that the program webcam on my HP computer does not turn on the webcam as usual, and when I click the ooVoo SHED , then said something to the first device is not found, then the camera is turned off in use. How can I arrange for you to use ooVoo