Videos Won't Upload Properly

[NatashaB16]

I've definitely used the right path because they're there in the sidebar, but they can't be clicked or anything, and I can't access them from my app- the folder's there, but they're not!
I can play them on my computer perfectly, but I need to see them on my app and they're just not showing up... I've deleted the folder and re-uploaded them but nothing. As I said, they can be played and downloaded, but I can't see them on the app, it's freaking me out!
Any help would be greatly appreciated!!!

[alphawave7]

Check your file's extension, and compare that to the list in Settings->General->Video Files...does it already exist?