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-Information FAQ http://forums.adobe.com/message/4200840
What are you editing, and does your sequence match your video?
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For CS5 and later, the easy way to insure that your video and your project match
See 2nd post for picture of NEW ITEM process http://forums.adobe.com/thread/872666
-and a FAQ on sequence setting http://forums.adobe.com/message/3804341