General Error when opening fcp project.

Hello,
I have been editing a project for several months now. Now when I open the project, I get the General Error Out of memory dialogue and my main sequence wont open. It is mostly mp4 files, which from research I now know FC does not handle well. I was able to work with it up until now so it was never much of a problem. The sequence I was working on opened a couple days ago but if I touched it I got the Error message and it went away. Now it doesn't open at all, the rest of the project is there just not the sequence I need. I just need to open that sequence one more time so I can export it. Please Help!

iMac 3.06ghz
4gb ram