Hi Gary,
Thought it better to put a fresh post instead of reply. Imovie is letting me import some .mp4 files but not others….specifically those I created from Handbrake. Does this have anything to do with 64-bit? When I tried to use Handbrake to read my dv, it prompted me to download 64 bit VLC player which I did, but I don’t see what the problem is with mp4s.
— Dhruv
.mp4 is a file type -- it can contain video compressed a variety of ways. My guess is that those .mp4 files that won't import are using a compression format that iMovie doesn't support.When using Handbrake, you can choose from a variety of format presets or customize your own. Whichever one you are using must not be compatible with iMovie. I think one is called "Apple Universal" format -- try that one to start with.