final cut pro x crashes

I've downloaded FCP X a couple weeks ago. I was excited to start working on various projects using FCP X. I edited one project in FCP X, I was happy with the, results editing on FCP X, when exporting as a Quicktime Movie, FCP X made a quicktime movie, which a made a copy on my desktop.

When trying to open FCP X to start a new project, FCP X crashes and will not allw me to use it. Can someone please help me with this problem!

Thanks,

Boscothree4