If you receive this error while in your course, please:
Clear your browser cache, and restart your computer.
If you need assistance on how to clear your browser cache, please click on the link associated with the browser you are using:
Internet Explorer: https://goo.gl/LQrknx
If clearching your browser cache does not work:
Please follow the instructions found here
As a last resort, please try downloading and installing the latest version of Google Chrome or Mozilla Firefox.