Click this link to watch a short video on resolving connection issues with Activpanel.
Video: https://www.youtube.com/watch?v=j2pJ8EssbQ4&list=PLTTWdUcy0p-5ACgumK-fShMVdYtgpQs5C&index=121
Reminder to contact the IT department if you are experiencing issues with a classroom Promethean.