If your institution restricts access to certain URL's, an admin or someone in IT may need to "whitelist" these URL's to ensure instructors and students can access the service being provided.
Extempore URL for Whitelisting:
How do I tell if my institution controls access to certain URL's?
Open this URL on your browser: chrome://settings/content/popups
The option to 'Add' will be grayed out if your institution controls access.