SOLVED. After dealing with this for months, reading these forums, and nothing working, I have solved it for my computer. I don't know why these settings weren't defaults for my after effects, but no matter what I did, uninstall, upgrade, downgrade, I could not import any type of video (mov., mp4., etc.). None of my coworking editors had this issue, so I compared every single setting with them. This is what I found. In my preferences, under "Output," my Conformed Media Cache was going nowhere! No path. So I chose the following folder and had to change the permissions from "Read Only." to "Read and Write." All of the sudden, I can add video!!    ... View more