"transfered it onto an external drive to free up space and then moved the final cut file back onto my laptop".
Something else happened. "Nothing" is not a correct response... moving the file off then back would not do this.
Try doing a "Software update"...
How are you trying to open the file? By double clicking on it? How about launching FCP first, then opening the file - or importing it...
I had created a FCP project on my macbook pro and then after I transfered it onto an external drive to free up space and then moved the final cut file back onto my laptop it said the file was too new for my version of final cut or unreadable. PLEASE HELP it has weeks of work on it. Hope you can help,
Mandi

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