Do you have GoPro software installed (with the Cineform codec)? If so, either try uninstalling the GoPro software to see if it's a conflict with it and/or try the latest available version of the GoPro software to see if the issue has been addressed.
Usually when the camera shows a "Camera is busy" message or doesn't show an image, there's some conflict with another application (Skype, etc.) that currently has access to the webcam as a video source). Are any other apps running in the background?