Uploading PowerPoints and Videos is a two-step process. You will get an error if you try to access them before both steps are completed.
1) The file needs to be uploaded from your computer to your platform. Depending on the size of the file, it might take a while due to upload due to internet speeds.
2) Once uploaded, they need to be converted into a web-friendly format before they can be used. Again, depending on the size of the file, this might also take a while.
We highly suggest that you add your PowerPoints and videos as early as possible to ensure that there is adequate time to complete the process.
For videos, if you are seeing an error stating The media could not be loaded, either because the server or network failed or because the format is not supported., please ensure that you have whitelisted the required domains on your firewall. For this error, whitelisting *.backblazeb2.com is the most important.