This model does not have a viewfinder and requires the LCD display to take pictures, so trouble shooting is difficult.

Turn the knob to "Auto" mode and make sure the shutter is not stuck. Take a few test pictures while looking INTO the lens so you can see whether the shutter closes and opens. Also Zoom in and zoom out to check if the aperture opens and closes.

Next, test the zoom lens is working and the mechanism is moving smoothly - without catching or grinding. The zoom can be knocked crooked, and can be very gently pushed back into place.