Directory error

so i installed unity 3d 3.0 beta or what ever and i try to open it and i after three timesd of opening it (i closeed and open twice in a day then one more time the next) this pops up creating directory library/metadata/00 failed please ensure there is enough disk space and you have permission set up correctly pls help

I had the same problem when sharing some code with another member on this team. I ended up fixing it by manually creating the metadata directory inside of the library folder, once I did that there were many more requests, but I just hit cancel to get through them. I think the project was expecting temp files to exist that didn't copy over, and because the parent metadata (and in my case cache) directories did not exist it wasn't able to work. Hope that helps a little bit.