Final Cut Pro keeps freezing when I export/render a video

[iPowers]

I've been working on some making some video clips that are ipod commericals (to eventually do the whole thing on imovie) but after 4-5 videos being finished, I work on the next one and right in the middle of rendering, it just freezes and doesn't do anything else, or when I try to just export it it does that, but before it works fine. I tried removing a couple extra effects I aded, and it still does it.

What is making it do this and how can I fix it, I have to get it done really soon so if anyone has any advice that'd be great! Thank you so much in advance.

 

[nyzwerewolf]

you should flush all the final cut pro preference files. if you need to know what files to flush, let me know. I'll look it up and let you know.

 

[iPowers]

you should flush all the final cut pro preference files. if you need to know what files to flush, let me know. I'll look it up and let you know.

Hmm what makes the preference files causing the problem. And yeah if you can let me know the files that'd be great! Thank you so much.