iMovie beachball on start up

Hi all,

I have a problem with iMovie that I can't solve. When I open the program up it almost immediately comes up with a window that asks "The previous attempt to open this movie failed, do you want to ignore it? Yes or No?"

Regardless of whether or not I choose to ignore it iMovie stops responding and comes up with the beach ball and I have to force close the program.

I tried to locate the .avi files which it mentions, but I think I deleted it from iPhoto some time ago.

I'm running a 3 month old MacBook Air, OS 10.8.3.

Any suggestions please?

Thanks for the help so far...

Have you tried deleting "com.apple.iMovie.plist" in Macintosh HD / Users / YOU / Library / Preferences / yet?

Click to expand...

I haven't got that exact file in Preferences, I do have this one though; "com.apple.iMovieApp.plist"

I can't tell what version of iMovie I have because it won't respond, is there a way of finding out which version I have without openining iMovie?

Trash is definitely empty.