Hi,
Firstly check your installation of Quicktime. You need at least V7.1.5.
It could also be a codec problem (though MOV is not a codec, it’s an architecture). Does you mov file open up in Quicktime Player? Or does it play back white? If it plays white, then you haven’t got the required codec.
Finally, it could be something as simple as a corrupted file.
You didn’t mention any error message in your post. Are you getting one?
If you’re still having troubles, uninstall and reinstall Quicktime, then After Effects.
HTH,
Ben
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