Sometimes organizations block certain URLs as part of their security. This troubleshooting is best for their IT team as they would need to add rules, and isn't meant for our actual users.

The site is hosted in Amazon Web Services. Some of the videos may come from:

I would start by whitelisting those locations. If somebody gives me some specific courses that aren't working then I can take a look specifically to see where those videos are being streamed from to be certain, but these addresses should cover everything. Also just keep in mind that Flash and JavaScript need to be enabled as well in the user's browser.

The courses are primarily built with software called Articulate Storyline. The courses themselves are zip files composed of HTML, JavaScript, CSS, and SWF (Flash). There are also some general metadata files such as XML and XSD. The videos are typically hosted inside of these zip files, but sometimes get streamed from a separate bucket. Those video files are .flv.