MP4's not importing?

I'm so confused guys! I tried dragging them into iTunes, no luck. I tried using the Automatically add to iTunes folder and it made these little subfolders by date that were all called Not Added! I've waited a few days to see if it just needs time, still not showing up. I was able to import a different one by opening it with iTunes but the show I'm trying to import doesn't open. The heck guys? What is going on here?!