Thank you
I've managed to open the file by renaming it, and I've purged it and checked for any problems (there weren't any)
its a 27mb file and its still abit slow and whenever i put shadows on it crashes, is there any way around this? all repeated objects are already components.

how do I disable my plugins?
ps. thank you both for your replies

i've tried that now, and it is still not working - it just opens and then crashes.
ps. i don't have any back up files or previous versions.

hi I'm using Sketchup pro 8 on a mac
I'm using a file which I think is corrupt, as it is only 22mb and it keeps crashing on opening.
I tried opening it and importing it into a file with closed dialog windows. what else can i do?