Adele,
Please ensure that the ActivDriver is up to date and try another USB cable connected directly to the board's electronics, behind the flame. If the issue persists, please contact Technical Support via the web form on the knowledge base at www.prometheankb.com, select your region/language, Interactive Displays, Contact Us. In the Existing case field input case number: 258104 also include the board's serial number.
Thanks!