When I opened iMovie 10, I had to force quit due to a hangup. The updating of my existing movies to iMovie 10 was interrupted and none were transfered. When I opened iMovie 10 I hoped it would start the updating process again but it didn't.
How do I get the existing movies into iMovie 10.
See the discussion at https://discussions.apple.com/message/23571280#23571280
It solved my problem.
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