This issue is likely due to a firewall your network has in place, try these options as a quick solution:
View the webcast from an alternate location
View the webcast on your mobile device, on cellular data. (note: data charges may apply)
Alternately, ask your IT administrator to white-list this domain: ce21media.streaming.mediaservices.windows.net
Note that this method will require you to reboot your computer to ensure the changes work correctly.
Please wait ...