This is a common error that is seen when you quickly switch viewing devices.
XFINITY On Campus only allows users to stream video to one device at a time.
First, make sure you're connected to your campus network.
If you switched from a computer to a mobile device, or vice versa, there may be a 5 minute delay while the video stream times out. Ensure that you have completely closed and signed out of one application before opening another. You may need to clear your browser cache.
If you're still experiencing an error after 5-10 minutes, please contact your university IT help desk support or submit a ticket through the XFINITY On Campus support page.