Spinning Wheel of death

I just tried to open FCP X the movie file which I have been working on for the past three months now won't open. Final Cut opens, the no file selected screen and the when the actual movie file comes up it gets locked into spinning rainbow of death and I am the FCP is not responding so I have to force quit.  I have now shut everything down and rebooted the whole computer two times. I have had no problems with this file up until today. It's a large file but that really shouldn't matter. Any help or wisdom would be greatly appreciated. 

Try opening the FCP by double-clicking the default Untitled library it creates in your Movies folder.
Then try opening the Library you need from inside FCP.

If that doesn't work, delete pref and render files.

If that does't work, open a backup (Movies > Final Cut Backups).

What computer, what OS, what FCP version? How big is big?