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-Information FAQ http://forums.adobe.com/message/4200840
What are you editing, and did you do this to be sure your sequence and video match?
See 2nd post for picture of NEW ITEM process http://forums.adobe.com/message/3776153
-and a FAQ on sequence setting http://forums.adobe.com/message/3804341
Also, The tutorial list in message #3 http://forums.adobe.com/message/2276578 may help