Chromebook file download @ University Online Meeting

Hello fellows,

every two weeks on saturday a friend of mine has a meeting with her university.
When the academics is uploading a file to download she isn't aible to download it with her chromebook.

Everything else works fine, but she can't download files they uploaded.

Her fellow students are aible to download it, but I think they use windows computers or macs.

The failure that shows in the buttom left corner at "FILES" is "unsupported content".

Does anyone have an idea to fix ist? Is there any way to get it worked on the chromebook? (maybe install at google chrome browser)

Thank you for your help!

Kevin